In quite a few
Scamp layouts, going into the center aisle covers the
furnace, so you have to choose between the bigger bed or having heat at night. That said, it’s a popular solution, as the linked thread reveals. As I recall the
furnace is under the forward dinette seat in layout 6, so it’s probably not an issue for the OP. Other things will be blocked, of course.
A
Casita Liberty 16’ or 17’ is the king of longways beds. You give up the permanent side dinette, but you kinda do that anyway with an aisle bed extension. Either way you have to do some shifting around to make a place to eat inside. With the Liberty you only have to clear the lower third of the bed to make a dinette. The 16’ was discontinued a few years ago, but used ones still come up occasionally. Selling a trailer for a good price is no problem right now; but finding the replacement is harder.
Our 13'
Scamp has the same rear dinette. My wife and I share the smallish rear bed for together time in the evening- watching a movie, reading, or whatever- but when I’m ready to roll over and sleep, I roll all the way to the front single bed (or the side dinette in your layout). That also accommodates nighttime potty visits and our somewhat offset sleep schedules. Works for us and keeps the limited aisle space clear in our 13’er.
Just some options…