Man, you’re not supposed to judge a book by its cover, much less its title, but when I heard “Throne and Liberty” for the first time, it immediately sounded like something lazily slapped together. I guess, it makes sense that specifically the localization is lazily slapped together.
Normally, the process is:
Having said that, I don’t know what you mean with “graceful”. Desktop environments may involve lots of packages, which may create configuration files in your home directory or get auto-started in your other DEs, so it can be messy.
Something minimal, like LXQt or the various window managers, isn’t going to cause much of a mess, though.
I guess, creating a second user with a separate home-directory, like the other person suggested, would isolate that potential mess…