here is my lattes model, an aurora/esci kit, (vintage 1977) scale 1/9 builded straight from the box and no weathering, i think these models looks better like that
A blackwash on the gun will help it a lot particullarly in the barrel vents. I would also put a little on the engine area but leave the rest like it is. Nothing wrong with a factory new look.
Maybe a little bit of metallic drybrushing on the MG34,but other than that I personally wouldn't touch it.You did a great job.
With the exception of the gun,maybe,I really wouldn't mess with it.Too nice of a build to take chances with.