Yep, with Vic and, yes, the wings are a big impediment when doing this. The other thing I did not mention in my tips is to keep the brush moving - you don't want to be hovering over a small area for too long. That floods the area with a lot of paint and makes for the different densities that you see.
If you already know that you may have rushed this then that's something you can easily fix, isn't it?. Take your time! I don't have experience with paints other than Tamiya over the last decade+ so can't comment on your mixture but 50% to me still sounds like a lot of paint for mottling. It should not be a matter of "wrong paint" as you suggest, but rather wrong mix ratios and/or wrong thinner. Unless you are using kid's water colours then most brands of model paint available these days should be OK in an airbrush, provided that you use the right thinners to match the paint. One size does NOT fit all in this case so make sure you use the right thinner! The nozzle clogging is a common hazard with acrylics and I myself end up cleaning the tip every 30 seconds or so. The other thing you can do is to add a drop or two of paint retarder which keeps the paint wet longer. Your local hobby shop should have some if it's a decent one.
Just seeing Yves' comment as I write, I'm not sure that I agree that 5-12 psi is too much pressure. Most compressors won't get much below that range anyway. But, if it's a single action brush you are using then, yes, that presents challenges as you have no way of controlling how much paint you lay down other than by keeping the pressure really low and moving the brush quickly.
The neat thing about German camo is that it came in a lot of variations and your result doesn't look that much out of place. However, if you want to tone down some of what you did, you could try going over some areas with thinned RLM 76. I think it looks fine though and is very good for a first effort. Once the decals are on, It should pull the finish together more.
