Maybe if you think of the resource as trainers it will work better. Neither horses nor wargs are like minerals, to be mined at a particular spot. They are animals that can be bred and trained in many places with the right resources, and the riders also need to be trained. So the spots on the map simply represent the availability of cavalry, not the spot where it pops out of the ground.

Wargs and horses should be different if only one is a horse and the other is sort of a wolvish sort of creature.

I like the idea of different kinds of horse/warg denoting their strength/stamina/etc. which would impact the quality of the cavalry units created with them.

That said, it's still an abstract representation like everything else on the map. I mean a herd of "real" animals should move around, migrate (especially in this world where natural prey/food is probably rare). Heck you don't even have to feed them! I had to feed my dog - much less if I wanted 100 of them to breed!

Even in the abstract horses are quite a bit different from giant, ravenous wolves.

wat? Nooooo Procipinee enjoys her giant wolf mount!

Yes. There could be attributes in the faction's designer, something like:

- horse man  (may use horse ressource)  cost: 1 point

- warg man (may use warg ressource) cost 2 point

- master horse man (may use horse ressource, may train mighty battle horses) cost 4 point

- master warg man (may use warg ressource, may train infamous wargs of xxx) cost 4 point

Playing as Ythril, in the late patch today [0.92?], I couldn't build riders even though I had the Warg resource hooked up.  Because, in the unit designer, both "Horse" and "Warg" equipment actually required the Horse resource.

I am seeing a disturbing lack of bears in this thread.