I think it would be quite fun if ground mounts can move faster. My other idea is some ground mounts get large jumps and some have wall crawling capabilities. It would be quite fun to walk up walls with a spider mount or do massive jumps with a horse mount. I like using ground mounts as it sometimes makes the world feel more massive and adds extra challenge, but its always so tempting to pull out a flying mount to save time. This would make using ground mounts a lot more fun and useful. Also. I would suggest a toggle for these features in case someone doesn’t want them and these features require the same things as unlocking flying.
*With some obvious restrictions for use in dungeons and other challenge critical areas.