daemons are horrible however in fantasy; instability needs a bit of a tweek as it's too crippling right now...
the undead can at least replace their casulties, plus they have lower pts values. daemons however have no way to 'summon' more but they all cost about 2-3x's the pts cost of undead! and their not that much better at fighting really... (they have a few neat tricks, but no staying power.)
couple this with little to no shooting ability, a heavy reliance on the magic phase and ultra expensive characters who typically use-up multiple slots! (ie: the cheapest daemonic hero uses 2 'Hero' choices!
)
cheers!