Good point Cor2,
For now I'm trying both solutions and still not decided, I will probably go with the most playable, fun one, but the point you underline is important as I try to integer the best my litlle mod in the Dom3 world. The fact of not killing horses would also simplify the unit and it's 'readibility' by players.
Aezeal :
I understand your point about straight not modded game, personally I'm developping this mod mostly for my own use cause I would like some east european mythology in the game

. About balancing the races : in fact I don't care too much when a race (or unit) is underpowered, I just don't want it to be too strong. Dom 3 races are not all balanced but after all Dom3 world is not fair and I like it that way.