I and many of us have had to go through the same decision making process as you. My decision was to buy a Suburban (I have a family of 6) and a travel trailer. My reasoning was I didn't want another engine and transmission that just sat around getting old unless I was going camping. With the Suburban I have a second vehicle to drive around as needed. I also considered that if the Suburban broke on vacation I could have it towed to almost any shop for repairs. If the motorhome broke I'd have to find a Motorhome shop and or possibly pay more for the same repairs.
But motorhomes have many positives as well. One of the biggest I see is you can just get in, turn the key, and go. This could also come into play if you want to stop at a highway rest area at night. If you decide something is wrong and you want to get out in a hurry you turn the key and go. If I decide I need to get out in a hurry I need to get out of the trailer and walk up to the Suburban to go. But in reality I think this is more of a fear mongering thought as I don't stop at rest areas at night. And when I have stopped in my car I've never felt like I had to get out in a hurry.
You could also possibly look into an older popup as it just doesn't rain much in So Cal. My popup weighs 900 lbs empty so your pilot could tow it. But it's really just a tent on wheels. It has no heater and it has no toilet. It has a dinette, a two burner stove and a small hand pumped sink and two full size beds. The positive is that you should be able to find one for less than $2,500. I only paid $650 for mine and it works just fine.
Have you considered where you're going to store this RV? That alone might help you make a decision as to if you want a second truck and trailer or a motorhome.
