Baron,
Ahhh,.... my little mig...*sniff*. It was one of, if not the, first kits i built on FSM..... fond memories there.
I agree with you that it is likely the wings were actually green and just a battlefield replacement of the original wing tip assembly. I have seen the b&w picture of that particular aircraft and came to the conclusion that the shading was too light to be red. It still remains food for debate, just going on that one picture....
Yet, i chose to paint them red as i felt it was more of a "russian" thing to do.... They seem to like red...red october...red this...red that.....
So in the end i made an "artistic liberty" kind of choice....purely influenced by taste. Your mig looks great btw!!
And as far as your question goes:
I have used a permanent marker in the past for preshading with pretty good results. Might be an alternative to not having to use an airbrush
And on behalf of washes: i personally like to use watercolors. Really cheap and almost as good as artist oils. I use a similar mixing as does Miss Owl with the exception that i also add a tiny splash of alcohol to improve the paint mixing up with the water. Watch out with the detergent in the mix as too much might cause your wash to bubble as you apply it too rough/ fast.
Apply generously... wait until it sorta starts to lose it's wet shine and then rub off excess with q-tips and demakeup pads. (always a good laugh to see the ladies at the beauty department give me funny looks when i go buy new ones)
Richard