In all honesty/fairness, Dual Pistols does have ammo that allows changing damage types to ice, fire, and toxic.
But it does that for all your powers and not select powers in the set. You could toggle it before using each power, I guess.
That's understood, but I'm assuming in the the other game that you don't have primary, secondary, power pools, and Epic power sets and are confined to the one power set, is that correct?
You seems to be cramming what could be pulled from a secondary, power pools, and epic powers into one primary power set, but I might not be understanding what you are trying to do.
The T3 you have listed as "Lightning Strike".
In regard to AoE Blind for a Blaster doesn't seem like a thing. I think the blinds are only relegated to controllers.
What do you mean by a Defense secondary?
You mean like a Scrapper Secondary?
Anyway, keep being creative. It's a good thing.