Nalia's not bad, plus you eventually get Imoen back

I use Aerie, but she is Dual Class, Cleric and Mage, and i don't need cleric so badly,
i just want pure mage.
It is pitty that i have allready inscribed all the spells i found till now in her spell book, i counted them, and there are 89 spells

Are there any "pure" mages npc "joiners" in the game, and is there anyway that i could export aerie spellbook (cheater) to another mage???
I don't want to do it all over again?
And yes, where is the Mordenkainen's Sword Spell?

I cant tell you where the spells are sorry. I never payed attention. Since i had sorcerer i didnt have to worry about getting scrolls. However it's best if you start as a sorcerer. Since that is clearly the most powerful class in the game(if used well). Other than that, edwin is the best pure mage. But he's evil MUHHAHAHAHAHA.

Hmm, no evil in my team.
Main character is Paladin, imported from BG1/TOTSC.
So playing sorcerer from the start is not an option
And if if edwin is a best pure mage in the game, i still would not use him, since he is evil

Don't you be talking about my old friend Edwin like that, he's a positive joy to be around! As evil as they come, delightfully wicked and blessfully good at keeping that oh-so-honourable beserker on his toes with witty repartee! The perfect accompanyment to my merry band of evil! *cackle* I'm still missing third cousin Xan though, perhaps he is somewhere to be found further inside the game. I miss his dulcet 'We're all doomed'.

Nalia and Imoen are the best. They both have thief abilities to compliment their mage abilities. Ariel is nice for the beginning, but she will never get 9th level spells in this game, and it would be almost impossible for her to even get 8th level spells. I am going to ditch her now that I rescued Nalia. As a cleric, the f/c combo of Anemoen (the dude in the Copper bar) is a better addition to the party. He specialized in sling, so he can sit at the back with his 100 hps and either support with the sling or cast healing spells. He is all you need in your cleric dept. The drow chick is actually a "better" cleric with her 18 wis vs his 12, but she has 35 hps less and the bonus 1 - 4 spells she gets isn't as important as his high HPs and superior combat ability. Plus he comes in at a higher level when you meet him and fit him with the guants of Dex you find fairly early, and he makes for some nice support.

Imoen is the best Mage for the party since her thief abilities make it so you no longer need a separate thief, but until I get her back I am keeping the bounty hunter dude - he's 15th level already and I am still in chapter 3!!!!

The optimum party would be your char as a pure half-orc fighter, Minc with girdle of hill giant str, the Stalker Ranger dude with the guants of ogre power (or the paladin guy), Imoen and Nalia as a devistating thief/mage dual class combo that whould reach lvl 17 to 19 in the game (I can smell those dual timestops already), and Anemoen as a cleric that will go to 18th to 20th level (holy word, gate, etc) and have enough HPs to stay alive in the rear supporting with nasty sling damage.

The multi-class combos just can't reach the high levels as fast, and you won't get to use the cool spells. IMO, multi-class is only good at low levels.