Thanks Peter2! Yes, GM skills are definitely something that make characters shine, and I found that it is easier to cast Day of Protection than, say, brew 5 potions of Fire Resistance. However, I played MM6-8 so many times I am mostly looking for challenge and fun at this point (like a 4 Knight party for MM7 or something). Too bad that potions and scrolls do not really level up with characters, and Warlock's familiar gives spell point regeneration and a +3 bonus to spells only I think.
So I guess no luck with knowing the actual statistics behind scrolls and wands?