I just found this list of enchantments:
http://guides.gamepressure.com/divinityiiegodraconis/guide.asp?ID=8320I suppose that is from before DKS, since in my game the values are +10,+20...+70
I think the values of that list are much more balanced. I don't even mean it to make the game harder, but to have more variety of items. + damage items on DKS just make the rest of the items worthless, and that's a bit boring itemwise.
And now a questtion, does the strength damage modifier affect +normal damage value? Or just the weapon damage.