I believe that a major selling point of Pixelmator is the ML tools included (Super Resolution, Enhance, Denoise, Match Colors). But with Photoshop recently supporting Super Resolution too, I think ML Sharpening in Pixelmator would be a welcome change.
For example, Topaz has a image sharpener that works great: https://www.topazlabs.com/sharpen-ai
I think having the same functionality in Pixelmator is absolutely needed.
What features would you like to see in Pixelmator Pro?