[Taqwus]

The crone, if memory serves, cannot wear armor. Granted, she has something like four misc slots, but still -- elemental immunities, good prot, etherealness, missile protection, magic resistance, luck will be hard to balance.
A lot of effects could be gained from casting spells, but that'll take up slots in your script and in addition may not occur fast enough if the opponent has accurate long-range attacks or can fly. These spells also can't protect against Seeking Arrow, Fires from Afar, etc -- for those you need gear or dome spells.