From left to right:
On the left I use shift, bksp, ctrl, cmd
On the right I use alt, ctrl, space, shift
This way the shift keys, by far my second most used keys on the thumb clusters, are always the closest one. bksp and space, the two most used keys, are on their original positions with the bumps to help me touch-find them. ctrl keys are right next to them because accidentally hitting ctrl doesn’t usually trigger any menus and therefore break my current workflow. The two most annoying keys to accidentally hit (cmd and alt) that also happen to be the least used are the furthest away to prevent accidental activation. Alt is still next to ctrl so it’s still easy to hit combinations with one hand.
EDIT: BTW I think a further improvement I can make is to swap my cmd and alt (so cmd is on the right half and alt is on the left). This will make hitting alt tab and also cmd + L (windows lock combination) with just one hand super easy.