A Character You Will Never Play Ever Again
Multiclass spellcaster, at least using the D&D 3.x/Pathfinder rules. (5e does multiclass spellcasting quite a bit differently, and though I haven’t had an excuse to experiment with it yet, I suspect it’ll play better than the older systems.) One of my current PCs is a multiclass cleric/sorcerer, and he’s in a great campaign, and I like the character a lot. But when combat rolls around, playing a multiclass caster becomes exactly the same as playing two characters who are slightly lower level than everyone else in the party, and who can only act on alternate turns.