Going along the lines of allowing a paladin to be mounted while using Lead (And Rally if it's implemented), I think it would make logical sense for him to actually get a bonus in using these abilities if he is mounted.... a paladin mounted on a mighty warhorse is MUCH more inspiring than one on foot, right?
I suggest the GMs fix the bug that makes it so paladins can't lead a group while mounted, and also... give them a bonus to lead (and Rally if it's implemented) while they are mounted.