I take your point, but I'm aiming high here and close ups are what I'm striving for-TRW rules! Priming does reduce the visual impact, but the lines are still faintly visible.
55 degree prints are definitely better for this hopper car, no discernable layering artefacts. I solved a few suction and support issues and the vertical lines are reduced a bit after leveling the plate again. What is interesting is the vertical lines are essentially absent on the inside surfaces and seem less prominent on one of the outer surfaces. It might be a visibility issue so priming is needed. I wonder too if more supports will help: I have none on the sides or interior. I might try that today.