You can cut the big chunk out of your modding. Your fort can naturally attempt to tame any Pet_Exotic critters they get their grubby lil' paws on, they'll just need to work up their skill with each particular animal type in time.
E: Some other stuff I figured I should add, although I'm not going to try to give a very in-detailed run-down of all the minutae of taming/training...
a) Exotic animals still may not be hunting/war trainable, it depends on the breed. But yes, if they were trainable for that before with a simple removal of the "_exotic" tag, they should still be trainable for hunting/war I think?
b) Taming (making a wild animal into a non-killing-dwarves animal) requires the animal to be in a cage, or... maybe on a chain? I'm not really positive, now that I come to think of it, since I always just leave them in cages after capture, until I get them tamed.
c) For training (taking an animal that doesn't want to eat your dwarves, and training it for hunting or war), you'll need the animal to be assigned to a pasture or chain, or make sure you add a "training zone," which is a new (i) zone. Kennels are now only used for capturing and taming vermin-type critters.
d) Pretty much all taming/training is now done via the animals screen, (z) (a).
e) You don't need a dungeon master, just one or more (I suggest more) dwarves with the animal training job enabled.