tl;dr
Is part of this proposal to roll back all rewards since the 51%?
That would bring back a lot of interest and faith in this project...
As it stands, the looming idea is that massive bag is going to be dumped on the exchange as soon as deposits are allowed.
It's an idea worth considering, but it has many implications. Coins generated after the 51% might well be in innocent people's hands by now; invalidating those coins would be counter-productive.