RV manufacturers are like realtors: they want to make sure everything is "neutral" and "inoffensive" to the majority of buyers. As soon as you get into any specific look, color or styling, you narrow the market. Whether that's a lot or a little limitation depends on how far out of the styling mainstream you go. One of my sisters-in-law loves the old farmhouse look, while another leans to chrome-modern. Where are you in the styling picture?
That said, you can buy whatever you like and redecorate at will. It doesn't need to come from an RV furniture outlet, so shop where you like. Most sofas and chairs come apart these days, to make shipping and delivery easier. Typically at least the back comes off, usually without much difficulty once you know the trick for that brand. The furniture stores can help.
You can also paint and wallpaper, change cabinets, and do most anything else you would do at home to redecorate.
