I try to make as few changes to shortcuts as I can bear not changing. And I try to make those changes as subtle as I can. So for example, Calva's hijacking of Tab drives me crazy, so I moved it to Alt+Tab. Not that much different. Worth noting that built-in keybindings mostly ignore the Alt key. So using Alt is a good way to open up more of the keyboard.

Sounds great to use ; and ` like that. On a Swedish keyboard , is a single key while ; takes two keys (`shift+,`), so might make more sense to use for me. , is seldom used in Clojure code anyway...

As for alt. Great when it works. For many keyboard layouts it won't work, since it produces various ”decorated” characters. Sometimes both the shortcut and the character is produced... This is probably the reason built-in keybindings avoid it. Calva used to have some default keybindings using alt plus some key, and it caused troubles for some users. For personal re-bindings, it's great.