About a feature request. I find it difficult to explain these things, but I made a picture. Hope you like the idea
The Spectral Paintbrush tool already allows this in a way. You can adjust the opacity of the brush and the more you paint over a region, the more opaque the selection becomes in that area. The more opaque the selection, the more any subequent edit is applied to that region. Here's a quick example:
Then, after hitting DELETE:
That is feasable, but I find it difficult to make equal strokes and if I try to "paint" a smooth gradient, I cannot align the 2 movements, so the line overlaps and the gradient is not smooth. This can be improved if one could paint with more than 1 strokes, adding to the selection. So I could make the alignment of the strokes more precise.