As a start, I'd take spells geared to your party:

Helps rogue: Grease, Web, Improved Invisibility (though...are there some druid spells nowadays that can make foes flat-footed?)
Helps druid: Honestly, your druid spells cover that.
Works well with witch's evil eye/debuffs: any save-or-lose spells - so glitterdust, slow, create minor pit
Helps everyone: Vanish, Haste, rope trick

So that gives:
1: Grease, Vanish
2: Web, glitterdust, create minor pit, rope trick
3: slow, haste
4: improved invisibility, and 1 more - maybe Shadow Conjuration for even more flexible options?