Admittedly I never liked a single "NEW GAME+" mode in general, I'm really not a fan of the idea at its core.
That said, I think it would be an exceedingly poor fit for a game based on D&D, where the struggle for progression is basically the point of it and where most creatures are supposed to have a certain pre-established set of stats and abilities, so inflating numbers for the sake of it wouldn't make too much sense.
The way I could see it is that a NG+ mode puts you back at level 1, maybe lets you keep your gear, but ALSO allows you to re-make your character, but also REMEMBERS your dialogue/moral choices.
It greys them out or otherwise marks them so you know 'I did that already', so you can make different choices without trying to remember every little thing you did.