Beware the Jabberwocky
Smash Apprentice
It wouldnt hurt, but would it happen? So far, Epona has been in three of the main "realistic" games. she has been a pretty big deal story-wise through out those three games. Though she is more or less a generic horse, she has made quite the impression in the Zelda franchise. I'm not saying that I would be overall upset to see a different horse than Epona, but I dont think it would happen... ever. They could get rid of epona in a game to make way for a new non-horse form of transportation (i.e trains, dimitri, etc.), but all horse-related transportation will probably be/look like Epona.