I've paid the $20 and have been experimenting with DuneonDraft. I don't mind the squares so much in there, and I do like that the scale is in-built. It's certainly easier than working in Photoshop. And I think you're right. I just find the pre-built stuff like Inkarnate so limiting, even if it's useful as a guide. Many of the authors I work with send me Inkarnate maps as reference for what I'm creating for them.

Painting with the clone toll is a neat trick! I need to give that a go.