Great start to your gallery! I think some of your photos have too much noise though. I guess it depends on the photo, but with PS I normally add 2-4% to my pics.
i started out using around 6% but lately if i use any noise at all it's around 2-4% like you mentioned.
i've been trying to use less noise in my photos and learn other techniques for making photos realistic, but i think 6% works well when you're trying to make a photo that looks like it sat in someone's attic for 40 years. (which requires an older vehicle).
i struggled with that 86 shot figuring out how much to edit. the raw shot from GT5 was very close to this; in the end the less i changed it the better it looked.
there's somethingmagic about deep forest between the tunnels.