You could consider I, J, K, and L. Those are the mirror positions of W, A, S, and D.
This is what Blasphemous does and I think it works really well. Just a thought.
Keyboard controls for action-y games will forever be the bane of my existence!
On the last game jam, we tried IJKL after switching from IJOK. With each choice, reviewers each wanted the opposite or they wanted the arrow keys.
...Time to make a script with all 3 options ready out of the box :P
Oh, and thanks for checking it out!