Downtheroad - Should like to see photo of your kitchen mod when you let the slides out.
Pump failed somewhere in Montana last year so we bought a Shur-flo at an RV shop in Billings. The guy in parts said to buy a "Silencer" which was really not much more than a length of braided hose as Sound Guy suggested. It didn't cost much and has proven effective. We just parked by the side and we replaced it in half an hour or so.
Larger battery suite, solar and LEDs probably only make sense if you are off shore power. We have used shore power once in last two years and generator not at all, so battery, solar and LEDs make sense to us.
Reed and Elaine