hello, i just for the first time today saw your post. to me looks good so far especially for your first ww1 aircraft. if i had seen this earlier i would give advice to not use tamiya paints to hand brush. unless you add retarder they do not work well. the problem is tamiya is not a true acrylic. its base is a hybrid and for some reason unless the paint is completely cured(perhaps a week or more) the fresh paint will melt the earlier layer slightly. this is ok if you use tamiya with airbrush. but when you use a brush the strokes pull up the earlier coat slightly which gave you your mixing effect. you can solve this by using a spray can clear or try different paints. i have found good results with pollyscale,model master. and vallejo acrylic paints. the best thing to do in my opinion is to inly use tamiya to airbrush but there have been some guys who can make wonderful things happen with tamiya and brush, it is just harder. keep up the great work i enjoyed your progress.
