Captain Picard loved his horse riding, even had his own saddle. Kirk loved his horse riding, had his own stable and horses. Horses by these two captains were a common trait. I haven't seen any horses on any planets. I'm not sure how you'd incorporate this, but I think it would be great to have Captain Picard's saddle. And I think it'd be great to have a horse in-game. A pet that follows you? An option to ride a horse? I'm not sure how it would be setup. But somehow, you have to bring horses into the game.