Assuming scrolls and "magical" arrows stay in the amounts that they are available in the full game, and that everyone can still use them - I don't see any reason to ever roll a Wizard from a meta-gaming perspective.
Clerics I might keep around, but not because I like the the spells they chose to include in the game, or because I need someone with revivify at level 5. Simply because of the magic items that combo with casting heals.
Hellrider's Gauntlets, Broodmother's Revenge and Whispering Promise makes every Healing word include Blade Barrier, Bless and a Poison Vial. But then again, I could simply put that on a Fighter and use my Second Wind for the same effect.
Yes on the cleric healing items.
From a meta gaming perspective though (the underdark sucks for sight and dancing lights/light can only do so much) Magic missile is fantastic, and being able to cast 2 per round with haste makes it better. If you are playing evil, Melfs poison arrow does nothing against certain enemies, so you need MM for ranged attacks since your 2d6 scorching ray bites if you miss. Not to mention being bait for everyone gathers all the enemies to you so you can spam items/barrels/radiance of dawn etc.
