Basically, I don't want to have rejection or loss of life in Creative Mode with this.

Essence is still present in Creative Mode, but you won't die or lose health or anything. None of the damage done by the mod is effective in creative.

Is there any creative behavior currently that you'd like changed? Otherwise I'll close this.

Now that I think of it, there should be an infinite Essence if you have a Creative Capacitor installed, even if in Survival Mode.