Not retired here, and generally heading to destinations 15-20 times annually, up to 1200 miles one-way. While I'm not the road warrior I once was, I'm still Ok doing 800 to even up to 1000 miles a day (example: Daytona to home in NJ - about 16 hours - leave at 5:30am and arrive home at 9:30pm).
We also like state and national park campgrounds, just about all that were originally constructed 60-80 years ago. Our 24' Class C does nothing exceptionally well, but isn't bad at anything either, and allows us to pretty much get into any place we choose.
It's a small house on a heavier E450 chassis, with shock and sway bar upgrades, so unless dealing with 30-40mph wind gusts, it drives reaally well. Those stiff springs do make it ride hard, but for me the trade-off is worth it. We have plenty of tank capacity to dry camp 5-6 days, and just enough living space along with plenty of storage.
We'll likely be replacing it in a few years, and are currently struggling with what to get. Likely might be almost the exact same thing, just with a slide, to fix that -just enough- interior room.
Whenever we are inside a pusher, the real estate is awesome, but there's no way one of them could get into the types of off-the-beaten path parks and forest service areas we enjoy.