Without really knowing what's going on with epic TR's it's hard to speculate.
However I'd like to see ED's tied to Epic character levels. eg:
when you hit 20, you have no ED's unlocked
when you hit 21, you get to choose an adjacent ED to completley unlock.
when you hit 22, you get to choose another adjacent ED
So long as there are less ED's than there are Epic levels, Once "cap" is reached, all remaining ED's will be unlocked.
The current ED grinding system is almost universally hated. This would let us choose my play styles as we see fit.
With a system like this in place, I would also be happy to lose All ED's when Epic TR'ing, so long as I can Epic TR the moment I reach level cap.