I see a few flaws that need rectifying.
First, the colors you selected are not accurate. Your underside is clearly Sky. You need to follow this scheme: Dark Green / Ocean Grey / Medium Sea Grey. Also, your interpretation of Dark green and Ocean Grey are not very close to the real shades. The green isn't olive enough and the grey need a bit of blue and to be a few shades lighter.
It should look very similar to this Spit 9.
Next, and I apologize for being harsh, but your paint wear effect is just terrible. I'll forward to you a PM from Greebo to me on how does his paint chips.
The first thing to do is examine as many photos of the type of aircraft in question as possible to get an idea of wear patterns. In general single seat fighters often show paint wear on the leading edges of the aircraft, particularly behing the propeller. The areas which are walked on by groundcrew (wing root especially) and around often used hatches (engine, fuel, oil, ammo access etc.) The edges of hatches often get chipped as they are removed or replaced and the areas around fasteners, where tools slip.
To create the chips I paint small (1-2 pixels wide and up to 5-6 long) light grey chips and use an eraser tool to soften those edges that are not up against a panel line. I place these up against the panel lines that are around the hatches as needed. Copy and paste is your friend here. Then I make the large worn areas on the wingroots etc in the same way.
I don't like the paint chips to overlap the panel lines themselves. Rather than place each chip really carefully I use a shortcut for clearing them from the panel lines. First create a merged panel line layer by copy and pasting all my other panel line layers into one. Next select this whole layer so all the panel lines are active on the screen. Then make the paint chip layer active and press the delete key. This erases any parts of the paint chips that are overlapping the panel lines. Once this is done, the merged panel line layer can be turned off or deleted.
Sometimes I create a scratches layer as well. These scratches are 1 pixel wide light grey freehand lines. Once drawn use an eraser tool to make the lines fade in and out along their length. Create a group of these and copy and paste this group over the access panels rotating the group 90, 180 etc to avoid it looking copied. Fade this layer until it is barely visible.
Once done the paint chip and scratches layers are copied to the specular map, lined up and turned white. The layers are then reduced in opacity (typically 50-60%) so they are not too shiny.
Please understand that this isn't personal. You're a talented skinner and with some more work, this will be a fine skin.
