The A.T. might consider a last revision of the 328-based UNO.
The breakthrough would be scrapping the linear 'LDO' (for 5V) and incorporate in its stead a DC-DC converter like we find in several of the new Nano products.
Users seem to need the power and they wouldn't have to rig up an external supply (which makes for a lot of unhappiness) - the "dissipate as heat" and how best to do it? stuff could be made a thing of the past (at least until even more power is needed).
The situation is certainly worse with the plethora of "Nanos", but that is no reason to make it worse for the Uno. In any case, I don't see the clone manufacturers rushing to provide a more expensive "Uno", do you, so the classic Uno will live on
As to me offering a genuine suggestion, it would be to retain the status quo
Not likely, with the '328 "not recommended for new designs". Now, release a 328PB variant, sure, but then, A-Star, right? So again, not likely. Why do what's been done.