For most of my work my post-processing is 'darkroom' equivalent - shooting raw and then checking the white balance, and levels/curves (in Photoshop terms). I'll often crop. If I'm trying to flatter a model I might do some minimal retouching. And that's it! I don't usually return to a shot once I've done this basic processing.

For digital art my starting point is usually a 3D render created in something like Daz Studio rather than a real-world photo