I had an old LT250R with a twist...and it never bothered me.
It was done up, ported, exhaust, Pod filter, bigger carb, etc.
The power delivery of a 250 and a banshee are nothing alike.
What makes a twist a bad idea is the lightswitch nature of a banshee powerband.
Seeing as how this is your first fourwheeler, and it's a banshee at that, I think a thumb throttle will serve you better.
Of course, that means a new cable too.
I rode CR dirt bikes for a long time, put a twist on my shee two years ago when I had similar mods as you, and It lasted about 2 rides (and a bent grab bar courtesy of my buddy) and it was off and a thumb put back on.
Swapping it out is not a big deal, just a pain to take the plastics and tank off....that's harder than actually swapping the cable in my opinion....