I prefer paint.net for asbuilts in underground construction. I use GIMP when I'm on Linux / MacOS but paint.net is a nice simple in between from basic paint-> photoshop.
GIMP is a lot closer to photoshop. Don't get me wrong - it's a great software but paint.net fills that role a little better for what I need to do.
I paid for and use parallels on my apple silicon laptop just for oaint.net
I've tried this. It's full of bugs and doesn't have any of the same polish or QOL features. Iirc it's an old fork from back when paint.net was open source.
I've considered contributing but I'm not experienced with c# or .net