I'm working on a small mod that makes several of the game's default enchantments from Cast When Used to Constant Effect or Cast When Strike. Does anyone have good guidelines of how much should an Effect be "nerfed", if at all, when switching to Constant Effect to keep it from being Overpowered? I'm mostly focusing on Stuff such as "Fortify" effects and keeping stuff such as "On Target" and "Summon" effects intact.

From what I understand there is a difference between normal enchantments and constant enchantments so it's hard to tell.