Re: Spells You Need to Choose, and Spells You Can Scribe
I'd take any of the "Must have" spells instead of hoping for a scroll (Unless they are in the fixed drops, obviously)
Off the top of my head, Haste and Missile storm are the ones I always have, although it's been a while since I played.
(Missile storm will, of course, save your butt in the finale and Haste is. Well, Haste)