Like Fenz said, just learn to love shift. I've set up my controls as follows:
(on all bars Fear/DP/LT/Cannib/WotF at the same place)
Bar1 (most used spells):
Wand, SBolt, Immo, Corr, DL, Fear, DP, LT, Defilers Talisman, RotV, Cannib, WotF
Bar2 (curses):
CoEx, CoA, CoR, CoS, CoE, Fear, DP, CoW, CoT, CoD, Cannib, WotF
Bar3 (more space):
DrainSoul, SP, Rain of Fire, Health Funnel, Drain Mana, Fear, DP, LT, ?? Cann, WotF
Bar4 (even more space):
Banish, SBurn, Hellfire, Siphon Life, HoT, Fear, DP, LT, Enslave, RotV, Cann, WotF
Bar5 (more..):
dunno, somewhere Corr rank1
Bar6 (more..):
dunno, think macros, SB rank7 somewhere, Demon Armor, Buffs etc
I've tried to keep similar spells on similar positions, so SP/SBurn/SB are all on '2', Drain Mana/Life on '5', etc. It takes a bit to get used to, but then you literally have all spells at your fingertips.
Edit: for pots/engi/etc I use autobar.