First let me post the starting stats my all-Drow totally munchkinik shamelessly min-maxed party.
Fighter 18/20/16/5/16/5
Broadsword - Mace / Throwing hammers
Paladin 16/15/12/5/14/18
Longsword - Longsword / Returning throwing dagger
Barbarian 18/20/16/5/16/5
Greatsword / Throwing Axe
Cleric 15/12/12/5/18/18
Longsword - Shield
(One level of Paladin)
Druid 18/20/14/5/18/5
Flail - Scimitar
Wizard 12/19/16/20/8/5
Short sword - Dagger
(One level of Rogue)
1/ You could pick a Druid as the last party member. Great healer. Great blaster. Great melee character.
2/ The argument of scrolls cost money therefore piking up sorcerors is not a good one. I normal mode I ended up with the best equipment of the game (including the uber-expensive bonus merchant stuff) and still had about 800.000gp. OTOH I do not use bows / crossbows / slings, those missiles are expensive
.
3/ Featwise. I am a two-weapon ambidexterity freak. Even the wizard has it. I also picked up Dirty Fighting for everybody (great skill). Every feat that enhances spell saves (Iron will,...). The spell casters have different spell penetration feats and one or more of the Spirit of Flame/ Scion of Storm/... feats. And of course weapon specilization in their favourite weapons.
4/ Skill wise. I avoided / regretted putting points in: Wilderness Lore, Picking locks (bashing them instead), Bluff, picking pockets.