Thanks! I haven't finished reading your post, but I'm just responding that #6, "Unlighting Textures" I was referring to removing light from photos so you can get cleaner textures for surfaces and add the lighting in game. I'm not even sure if there are any good tools for that one. Aside from a general paint editing app.
Also, no, I'm not looking for a universal app to do all of it. I just want to know what some of the move common/respected tools in the industry are.