WARNING: Do NOT attempt to install ANY other desktop environments next to KDE Plasma Desktop. This scenario is NOT supported and you will be told so in no uncertain terms if asking for support.
Can't say nay, but you know... budgie and gnome has incompatibilities when installed at same time, mate and i3 has none.
If you're feeling adventurous... go play skyrim. Just kidding, make a backup and try, we cannot succeed without failing.
edit: backup your home folder, or create an new partition in your hard drive, name it something like DATA and send your important data there, then you'll never loose your files if messing up with your OS... you don't need to copy or move your data back to home, just symlink them to home... just ask if you need help, it'll be a long tutorial.