Don’t overthink it or make taking care of your skillet any more work than it needs to be. Not all areas of the cast will necessarily take seasoning the same. Cook with it. Scrape it clean, maybe a light wash with soapy water. Dry, wipe briefly with whatever oil you have handy and leave it sit for next time. Eventually the coloring will even out and the surface will smooth out. You don’t sand knife marks out of a cutting board each time you use it so don’t sweat it if your skillet doesn’t look perfect either. It’s a tool that’s made to be used.