It would be amazing if we could edit the strength of a brush immediately after making a brushstroke.
For example, say I just lightened a face in an image but then decide it's too bright. Rather than having to undo, try another level of strength intensity, repaint and see how it turns out, it would be way better if I could just adjust the strength slider and see the brightness edit I just brushed adjust automatically as I slide the lever, so I can correct after the fact as needed, and get on editing.
This could also be applied to changing the last brushstroke from "Highlights" to "Midtones," for example.
This would take the labor-intensive guesswork out of getting just the right strength level.
What features would you like to see in Pixelmator Pro?