What draws you to different distros? I get my thrills switching between GNOME and KDE on Debian every now and then ;) I guess you'll get good at isolating your dotfiles and other configuration tweaks.

I'd want to try out

- Tumbleweed (rolling release SuSE)

- Mint Debian Edition

- Arch, to see what the fuss is about

- NixOS

- Zorin, or another "easy listening" distro