If you really take the time to read what was really "prominent" was the commemorative medal or coin as using those mint figures. It didn't really make any mention of anything relating to coin production.
In 24 years, the Treasury Secretary can change the design on the Jefferson on his own authority, and the presidential dollars will go away in about 12 years (give or take - depending on how many presidents we elect and who dies between now and then).
I'm not sure, it would really depend on how the legislation that forced the return of Montecello was worded. At the time the Act of 1890 was passed, the coin designs were pretty much left up to the Secretary of the Treasury but he was still restricted by the laws that stated what mottos had to appear, that coins larger than a dime had to have an eagle etc, but he could choose the actual images used himself. If the law mandating the return of Monticello says something like " the reverse of the five cent piece shall bear the likeness of Monticello" Then the Secretaries hands are tied. He can give use different views of Monticello but Monticello would have to be depicted on the coin until new legislation removing that restriction was passed.
That's what I was thinking of. Sure, it would still have to be Monticello, but it could be from the side, or above, or the view when sitting in the outhouse out back. Not the change we would like, to be sure, but change none the less.