I have concluded that Jaheria is just not a good character despite what people think. Let's consider why:
1) Druid weapons are comically bad in relation to what other weapons you get at the same time, so basically you should forget about meleeing.
2) Her proficiencies are all wrong to begin with.
3) She has 15 strength, not enough to get a strength bonus or make use of the strength-enhancing sling.
4) She has a low wisdom (13) which gives her only one or two bonus first level spells.

Ok, some of you think she's great as a druid. But compare her with Cernd, the shapeshifter:
1) Cernd is a better fighter at close range because of his werewolf form. (he tore apart the evil druid master)
2) Cernd is a much better caster, with 18 wisdom he gets 5 additional spells (2 first level and 1 more from level 2-4).
3) Cernd can have a decent armor class when you give him the +2 AC healing staff and bracers, which strangely don't count as armor (unlike with the kensai). Besides, with stone skin and the like, he shouldn't be taking damage, and he can rejuvenate with his other staff.
4) Cernd can claim the druid grove because he can reach level 14.

Not necessary true, since Jaheria is a fighter/druid (more diversified), she can wear both heavy metal armor and carry large shield, give her a good club or scimitar will make her a decent tank. And I don't think the bonus spells are really to much of a factor, since I only use insect plagues and elemental summoning from my druids most of the time, the key is choose the spells carefully. And both characters (Jaheria and Cernd) can regenerate so long as they have the right items. But I think in order for Cernd to regenerate, he needs to be "using" his staff rather than just having it sitting around in his "other weapon" slot.

Equip her with a belt of hill giant strength and a decent club, preferrably blackblood +3. Now she's doing around fifteen to twenty damange per swing and has a fighter's THAC0, and unlike Cernd, she doesn't have to shapeshift back into a normal form every three seconds when she wants to cast a spell.
Cernd can't claim the druid grove, he's an NPC.
Cernd's armour class doesn't even come within a stone's throw of Jaheira's, and his HP is terrible.
Finally, Jaheira is about a hundred times as interesting as Cernd. She has innumerable side quests and a romance string, and you can actually understand what she's saying. I'll sacrifice those first level spells for someone who can fight and tank for me as well. A pureclass druid is very much a waste since they can only get to level fourteen, at which point they still have very few spells. If you can't see why Jaheira is one of the best NPCs available, you're simply not using her properly.

But in order to make Jaheria a front line fighter you have to give her the hill giant strength girdle. It's better to give it to Keldorn or another tank who have better weapons available (especially if they dual wield).

I haven't experienced how powerful the shapeshifter is as a greater werewolf, but I suspect Cernd will be at least as good in damage output when you dress up Jaheria. The truth is anyway, I find druid's proper role is not up in the front lines where the can't cast when they get struck. I found that Jaheria was just sitting back to cast her spells, and I might as well have put a better caster in her place. Cernd shapeshifts after he has cast his spells or if the party is jumped from the rear as a defensive measure.

I think a big reason for me is her personality. She snipes at every other female in the party and is just annoying, whining, and humorless. As for the level 14 cap on pure druids, when Cernd gets long in the tooth and those insect spells get resisted a lot, I will just call on Viconia who can emerge at a high level, having never joined the party. (Or even Amoen, sigh)

Anomen.....ewwwwwww
Personally, I enjoy declaring to him that I am a force of evil in the Copper Coronet (where he leaves), then go to government district and slaughter everyone (including him) in his house.(No reputation reduction, and he is actually the one attack me first.)
Or, accept him into my party and make him fail his little paladin test.
(Yes I know I am a sick b**tard, but this is what you get for studying in accounting for 4 years)

For argument's sake, let's take my party - me, Korgan, Jaheira, Viconia, Edwin and Jan. We can ignore Jan and Edwin, since they don't require any stat-boost items to be good at what they do. Now I'll give Jaheira the girdle of hill giant strength and myself the girdle of frost giant strength later on in the game. Korgan can have the gauntlets of ogre power. Jaheira is now sitting in the front line with her fantastic armour class and iron skins doing 15-20 damage per swing and missing once in a blue moon. Korgan's either clobbering people from long range or beating them into pulp at close range; he's excellent at both, and does great damage either way. I'm doing my fighter/mage thing.
I don't make the Crom Faeyr. It's the best weapon in the game, but nobody in my party has a use for it when we'd be just as well off with two extra strength boosting items.
Even as a greater werewolf, Cernd barely ever hits. I know, I've been there.
You're still only seeing Jaheira as a druid, while I look at her as one of my fighters. Like I said, you're not using her properly.
As for her personality - everyone complains about this. I still don't see why. She doesn't whine, she didn't annoy me, and she's the only character in the game who actually laughs at the protagonist's jokes.

In both my games, with a kensai-mage and a blade, she doesn't have a place. The blade needs the girdle, and with the kensai's party, he is surrounded by other competent tanks (Yoshimo dual-classed, Keldorn, and Minsc).

That's fine. You're saying you don't use her, and I'm not going to hold that against you, but just because you don't put her in your party doesn't warrant unilaterally deciding that she's completely worthless.

Jaheria like Minsc isn't about stats and abilites, if you want the best stats build your hole group yourself, you deck out a group that can trash any NPC group. But Jaheria and many other NPC's are about the fun they add, with her bitching, trash talking, love interest it makes the game more interesting. And why are you playing for fun, or just to trash the monsters easlily.

yeah, you have to use Jaheira's advantages as a fighter/druid,
In my game she has a -10 AC and uses a +5 sling with a gauntles
of ogre power, makes her a great ranged fighter, plus her excellent
druid spells. In my opinion she is the most complex npc in the whole game.
If you dont have her it's a pity...

I agree with ironfist. Jahiera tanks up well. So what if she can't make full use of the strength enhancing sling! it's not the best sling anyways. Give me the +5 sling any day! It doesn't need any ammo!!! Arm her with the Blackblood +3 club or the +2 Belm scimitar (+1 extra attack), the +5 sling, and the fortress shield and you have a very capable 3rd fighter!!! At least that's how I use her.

Oh, ad by the way, Insect Plague is a major kick-ass anti mage spell!!! And her ability to summon Fire Elementals and (later) earth Elementals is better than those that any mage can summon. (I like my summoned elementals to be under my complete control without having to wait an extra round to bring them under control.)

Jaheira does rock for all the reasons mentioned so I wont deliberate further on her.
Another point against Cernd as a Greater WW aside from what Armisael mentioned is that his AC sucks big time and there isn't anything you can really do about it. Even as a GWW he is going to take alot of damage, whereas Jaheira with a -10 or -11 AC doesn't get hit very often.

Well, I'll try keep Jaheria in one of the parties and dropping Minsc for Edwin or something. That'd be a party of neutrals and evils only.

Jaheria is great.
She is the leader of my party.I think shes the best leader you can have becouse she haves a 15 charisma and party npc likes a high charisma leader , and jaheria is only one fighter with a high cha.
And my Jaheria has a Spear of the unicorn and does around the 15 damage a turn , most times more then 15 and she haves a Ac of -18 !!!.And if she cast spells I let cast her most times call lightning our heal spells.But the 18 ac is nothing with the -20 of my loveley Aerie.And jaheria is a nice Npc , she is a little bit my Mother.

G.W. Druids are better if they are multy our dual classed , and Jaheria can shapeshift too , in a bear and brown bear and wolf , these are not the strongest , but its better then nothing.

Jaheria is Cool , string and you can have interesting conver. with her without falling in love.

I mean strong .

Maybe it's just me but please tell me this: How the **** do you get an AC of -20????????????????????????? Well or even -18 for that matter. The best I ever got was somewhere around -10

If a blade uses a combination of maxed dexterity, armour spells, bladesinger chain and a defensive spin, you can get their AC down to around -15. But it's impossible for Aerie's AC to get anywhere near -20. Even with all the spells in the book, the best armour she can wear is the robe of Vecna, no shield, no helm. With about a minute's weaving time and the best equipment available, she might get her AC down to about -10 if she's lucky, but I'd doubt even that.

I think armor is too low in this game. Ive just started playing with my sorceror (i have spent 10 days 17 hours in game-time) and ive already AC -4 !! which is pretty fine for a mage I think. All of my characters have already AC 0 or less except edwin. But maybe its right cause i hope i will find level +15 enemies, maybe level 20 so I´ll need a good AC.

Yes when I'm referring to AC I mean the permanent AC, so not the one you get when you cast this or that spell. So just with items, what's the lowest AC you can get?

Lowest I've seen was around -14. That was Jaheira with drow plate +5, a big shield and a good helm.

Only -14 ?!?!? In IWD i could get around -18 or -20. And I really hope that in BG2 I will find better items than in IWD.

And I made a mistake. My sorcerors AC is -5, but maybe Im playing wrong giving all the protecting items to my character instead of making Minsc and Keldorn be tanks. Anyway, I like to fight and get involved with my character, not sending NPCs to fight while i watch or simply cast a magic missile. I even have removed the sling +2 from my character and now he has only melee weapons. And he isnt having too much problems, using stone skin and mirror image while fighting and casting. Thats real fun !!

I can get down to -15 with Viconia and none drow armors.
These items are: Red Dragon Scale, Helm of Glory, Ring of Gaxx, Ring of Earth Control,
Cloak of the sewers, Amulet of Protection, Saving Grace.

Jahiera is a good character because of her versatility. She can wear all the armour, cast lots of good spells that other characters don't get and she fights pretty well with either the club blackblood or the +3 scimitar. I think she also has the most detailed npc. A lot of special events revolve around her and she has a lot to say. She's the most fleshed out character so to speak. I don't even give her strength enhancing items. Viconia has the strength 19 girdle so she can actually wear decent armour. By the way the best armour class in my party is -12 on Jahiera with drow plate (in chapter seven), baldurs helm and shield of harmony. The lowest in my group is -4 on Imoen just with drow chain +5.
ARMISAEL- Aerie can use shields and helms. She's got a -8 AC in my group from drow chain, helmet of defence and sentinel. Carries the mace maulers arm so has the strength to use better armour. Can remove weapon and will still get AC benifits from armour even though you're now too weak to use it. Aerie is a cleric too remember.