NOS makes an octane booster that incorporates nitromethane for actual, honest HP increases (tiny increases, but real).

Don't try removing the ethanol, it won't work.
You'll wind up with low octane or some weird concoction that won't burn right...or no change in the fuel at all other than the extra cost of the additive that's not doing a damn thing but being a filler.
If you mix something in that's supposed to neutralize the ethanol's effects, you need to know the exact amount of ethanol in the fuel.
That brings you right back around to this point:
There's nothing wrong with ethanol in fuel!
It's the AMOUNT of ethanol that's in there...if it was set at a precise mix, then there wouldn't be a problem.
When you buy pump gas with ethanol, you don't know how much is in there and you don't know how to jet accordingly (ethanol mixes change the stoichiometric ratio).
Ethanol by itself is great for racing and will produce more power than gasoline will.
It also needs somewhere around a 9:1 ratio to burn correctly, which means it'll lean out your carb and melt a piston if you don't re-jet.
Buying pump gas is a lot like getting a jug of premix from a dirtbiker and dumping it straight in your tank without asking what the premix ratio is...except that if you ask the gas station how much ethanol is in there they won't be able to tell you.