ToME: the Tales of Maj'Eyal

Should points be redistributable when you are playing nightmare difficulty?

Absolutely yes! Certain builds rely heavily on point redistribution.

Yes, because there's already heavy boosts of enemies and part of the fun of Nightmare is using highly powerful/abusive setups, as normal, and still being challenged.

I don't feel like the player end should function differently on Nightmare. That's what Insane is for, maybe there. Then again, Insane already is really nasty and has literally as many clear cheaters for clears as it does legitimate clears. (Seriously, search Insane/Roguelike and look at the results.)