Nah I just have a couple of strategies for dealing with being faced by either material or non-material unexpectedly.
If I have Fireballs scribed and I bump into a non-material mob, then I either chuck the Fireballs and quickly replace with Harm Non-Material Being or (usually if too low on mana) run away, chuck the Fireballs, and replace with Des Ew.
If I have Harm Non-Material Being spells scribed (usually because I've already seen at least one non-material mob in the area) and bump into a material mob, I either chuck the Des Ews and quickly replace with Fireballs, or run away, chuck the Des Ews, and replace with Fireballs
And as for Vorpal Blades? Bah usually can't be arsed to waste the time changing weps so I just deal with non-materials magically
Ah well, it works for me at any rate...and besides, the only place in CSB I can think of where I meet both materials AND non-materials in the same room is the Fire Elementals and Demons in the DDD (in which case I can easily prepare to attack the former), and Ghosty-thingys and Demons on level 10, in which case I hide at the top of the stairs and zap them for ages before getting bored and running away to take another route up

. Still haven't finished it lol.