Another lefty here, and way too old and no interest in changing. I also use arrow keys as wasd and use del/ins/home/Pgup keys as my hoykeys... I even use some of the numpad like 0,1,4. All are easily bindable in this game EXCEPT..
I get a second full set of keys (for me it's my healing set) using my right thumb on control and using the del/ins etc for a second bar's worth. Problem? control pageup is irrevocably set to control chat scrolling. It's not on the list, and rebinding that exact function (chat scroll) to a different throwaway bind does NOT change it, so everytime I use my long cooldown second interrupt (bound to control Pageup) I not only get an interrupt, I also scroll my chat up... and up it stays till I remember to scroll down and re-read the conversation I missed for the last who knows how long.
Undocumented keybind that can not be changed?? really? c'mon guys.... is being able to page scroll through chat all that important? End doesn't do that... I know it's bound to tab target for me. Control home doesn't affect chat, just my aoe knockback....why can't I decide to rebind ctrl-PgUp?