I can't help you with most of your concerns and questions, but can offer comments on two topics.
Size / Class B vs. Class C, etc.: My wife and I (only!) have traveled over 40k miles in our RT09/10C190P, our longest trip being around 4 months. Sorry, but I can't imagine traveling with even one more person, let alone two or three for very long. YMMV! I do agree that having a smaller unit is highly advantageous in many situations: we were (barely) able to negotiate the famous, downhill, winding block of Lombard Street in San Francisco! If parking a longer/wider unit at your house is a major show stopper, as you indicated, perhaps you can find a nearby storage place for it?
fridge / 3-way or compressor: I wouldn't base my choice of a rig on this criteria. We have a 3-way, and have NEVER used a single one of our couple dozen "Lego blocks" that we've lugged everywhere, and never had much trouble getting "level enough" in any of the campgrounds, boon-docking spots, or roadside spots we've camped in. I think that two or three times in a hilly Walmart (or similar) parking lot, we had to hunt around for a semi-level spot. Bear in mind that being enough out-of-level for the 3-way fridge probably won't be real comfortable for sleeping either. And finally, a number of people have changed out their 3-way fridges for a compressor unit; it ain't rocket science.
Best of luck, Dick
