In my opinion your tail fin mottling was quite good, and I liked it better than the solid green/brown, definitely.
Sorry I haven't been faster on the response, to go back to the devil's advocate in viewing those photos, you can't tell from that one photo what color is on the nose because the colors have such little contrast. Even the darker 2-tone mottling is barely distinguishable from monotone spots. One of the hazards of WW2 photography, which was a technology still developing at the time.
I think you've done a fairly nice job. I think you still need to work on some of the details here and there, tweak them, etc. Some things Ink has touched upon already.
However, I'm stuck every time I see it thinking it's too brown. You say you got your shades from Simmer's Paintshop, and this is one of my major beefs with that page: The paint chips are terrible!
I've seen tons of photos, I've handled recreations of the pain colors myself working with scale models, I've seen a lot of more thoroughly researched websites showing better colors. I've tried using Simmer's chips and the end result is always terrible. Simply swapping out the colors for those on better references yields greater end results without doing anything but changing the color!
Here is an excellent reference link:
http://www.ipmsstockholm.org/colorcharts/colorcharts.aspThe Germany section can be found here:
http://www.ipmsstockholm.org/colorcharts/stuff_eng_colorcharts_germany.htmNaturally these are just the base colors, and you can have a large variation on any one of these after you apply weathering and other layers and effects, etc, but they should be your starting point.
For the standard RLM74/RLM75over RLM76, it will be better to use the following:

Upper left: RLM74 Graugrun, upper right: RLM75 Grauviolett
Lower: RLM76 Lichtblau
I've uploaded a few of the common colors for LW aircraft here:
http://www.nakatomitower.com/models/colors/The more I look at it, the more it looks too much like an end-of-war K-4 with brown paint rather than a G2 with overspray. It should be more of a 2-tone grey than a grey/green, and the over-spray most likely RLM02 or RLM74 (both chips included in the link above). If you wanted to go more brown-tint, RLM02 is the way to go (I find a slightly darker/weathered version of the paint chip works nice). Mind you this isn't anything against the work you've done so far, just the colors of that work. It's easy enough to tweak if you've got the layers separated (as you do). I've done the same and had the same suggestion made to me a number of times, so it's nothing personal. I just don't think the colors are right.
Otherwise the work so far has been good and it's something I'd fly in the MA, for sure.