Indeed the speed factor is definitely a part if them 'perks' they should have over rentals.

If I remember correct-like, it is possible to make them at least as fast, but it will be all it is: fast. Good for the races, no good for digging, which I also liked to do quite a bit (the Hot & Cold game, actually; I still occasionally do that for no particular reason (not for the items at least, aside from fish-tank items recently)).

Indeed, the raising part certainly could be made more accessible, too, even via minor tweaks.

If it was effortless to call the chocobo repeatedly, I think many would still use them when moving around in an area (if it were to be faster than by foot at all), but yes, all the fast-travel certainly made the world a small place. :\