If you want a quieter watercooling setup, try adding more radiators. Be sure there's plenty of natural air circulation over them or add fans as needed. Any radiator that doesnt have an exhaust fan should be outside of the case, or it'll raise your "ambient" system temps.
I think people in the forums have mentioned automotive "heater core" style radiators which are compact and designed for swift dispersal (they are what the engine coolant runs through to heat the cabin). If I'm wrong about this, please somebody correct.
They're designed for quick radiance with high power fans, I think their fins are too close together to operate well with just house drafts. I'm not sure what would be best for that but I saw a circular solution intended for farm machinery that had the right idea, it would create its own air current as heat built up in it's center area.
Simply moving the main (pump and) radiator outside of the case should negate the need for most of those other fans you mentioned, assuming you have decent insulation on your water lines.
