Rate from 1 to 10. Tell me what I should change, if anything.
Not OP but I was able to play osu! fine on Linux after just disabling the mouse acceleration worked for me. After that, it's just a matter of adjusting the in-game sensitivity to try to re-create what you had on Windows.
Keep it as-is, except my system has 22GB of RAM. One streamlined panel and a hideable dock is splendid.
I used these: https://kizo2703.deviantart.com/art/Windows-classic-theme-for-Windows-8-RTM-8-1-10-325642288