The ESP Bangers were pretty good driving putters but they're OOP now. I agree that the Aviars are just taking up space, I'd at least try and trade them for some Bangers to have a practice stock if you want to commit to the Banger.
FH the Sidewinder and BH the River is interesting b/c those two aren't that dissimilar stability wise sometimes. If you want to reduce a mold you could probably find a new SW to replace the River or more likely a beat River to replace the SW.
I'm somewhat surprised that you FH only for distance. I'd tinker with a lid like a Polecat or Rattler, Sonic, etc b/c they can be fun to flick on approaches. It's a lot easier to lower scores by concentrating on that approach game instead of searching for that magical distance disc unless you're a strapping young lad.