Mine on the 2002 Plus8 were smoother than that. Same style. The powder coat on the inner surfaces was starting to deteriorate and some peeling off. I sanded the insides back smooth, primed and sprayed with silver rattle cans to as good a match to the outside as possible. I then waxed them to make cleaning a bit easier. The insides were easy to do as less fiddly areas. A pro would sand/soda blast back to bare metal then finish.
I did also consider trying a Plasticote type spray on to see how they looked in black. It's a peelable coating so easy-ish to remove if desired. It's similar to vinyl wrapping but sprayed on. Built up coats to add depth/strength. A bigger job than the insides as a top finish is the aim so a lot more fiddly prep. The cast in lettering would be awkward, probably needing solvents to remove the coating. Didn't do it as the car was sold.
