Personally, I have next to zero concern about the command tax in cases of infinite mana combos. If someone is generating infinite mana and can recycle their commander a bunch of times, winning any other way would be trivial. Besides, nothing about that is casual. It's very much a situation covered by the 'If people want to break the format... It's clearly broken". I hardly see the benefit to changing the rules for those cases.
Now, I could still see changing the rule in a way that deals with that, but more as collateral damage then anything else.
Look, the problem is less people doing broken stuff with their commander, and more the fact that removing the commander is useless as it immediately comes back. The Rules Committee clearly does not want you to be able to completely and permanently banish Commanders, or else tuck effects would still work. So really, the goal of the command tax rule should be to make removing the commander give you a temporary reprieve from dealing with it in play, and obviously a meaningful challenge to the persons who's commander was removed.
The best I've seen is basically setting the rule so once your commander is killed, you have to go a turn without it. Something like if your commander is returned to the command zone, it is done so face down (can't be cast) and at the end of your turn it is turned face up. Basically, the commander being killed forces the player to go a full turn cycle without the commander in play. Sure, it deals with the stupid infinite turbo-recasting the commander several times a turn, but thats hardly the goal (mainly because that goal isn't worth caring about). Forcing a full turn cycle without the commander seems like both a meaningful speed bump, and not a complete shutdown like tuck effects used to be.
Of course, commanders with flash and ways to give your commander flash become significantly more powerful, but I don't know that there's a perfect solution to that. It also makes the commander prison cards (
Darksteel Mutation ,
Imprisoned in the Moon ,
Oubliette ,
Song of the Dryads and the like) weaker as well.