It'd be nice to have "rothe meat", "rat meat" and perhaps even grubber or deep hound meats as reagents for the "animate dead" spell. It'd be wonderful to have some variarity plus it'd be an even bigger insult to nature-inclined Druids and Protectors and ground for further conflict. Rats could have on-hit disease properties and dexterity stats, whilst Rothes could have ridiculious hitpoints but low AC/Str, for examples.
I'm especially looking forward to undead hounds, I think that'd be a really stylish and cool option. None of these should be more powerful than warrior bones though, I feel.
there used to be undead cats on efu:a i believe and even in efu1? wouldn't be hard to add animal corpses if desired
A Blighter Druid kit where you gain your spells for destroying vegetation, and summonings/companion animals gain the undead template...