The question you are asking is definitely going to be biased being on an RVing forum for sure.
Two totally different ways of travel! What in your hearts do you really want to do? As that is what you will do. Personally we'd be saving our free flight miles towards somewhere we couldn't get to by Motorhome ie; Hawaii, Islands etc.
You say you are retired, why wouldn't you take your time and smell the roses along the way and make the most of the various other places you can explore and stop and see rather than just the destinations?
Just sayin'