I really prefer buy from the store mounts and click to learn also the click to use option. Maybe some cool animations for the different mounts. Horses can gallop to you. Dragons(and any other usually flying creature) can fly to you. Cat-like mounts can jump from behind your back. Wolves can jump in front of you and huss at you. And all that for the period casting time. As riding training I think it would be cool to be obtained via small quest and a fee like irl where you have to pay for your driving license and actually attending to some classes . Not sure will there be tiers of mount riding skill but if there are I prefer for them not to be really expensive. Of course higher tier should be more expensive but still affordable š . And if there are gonna be riding training tiers. Maybe upgrading your slower mount to a faster one seems good. Like your car irl - just tune it. This could be obtained by another quest. "Mount tuning"
As for mounts having different abilities seems cool to me. Every mount with wings should be able to give you slow falling. Horses should be 10% faster. Some water-like creatures should give you water speed. And so on. Also mounts should be disabled inside buildings but maybe not every building there should totally be places where you can ride inside.
Also I think every race must have unique mounts with different skins without any bonus abilities ( because people may decide to use a certain race only because of their mount) but just another skin added in the market for everyone to have. Like if humans have horses orcs should also be able to have a horse, just like bearan, undead etc. But only 1 limited skin.
Ok i think that's all I could think of š
Cya around!
Regards,
Shock! :)