Heh, I was aware of the blue/yellow Eldar colours long before I was aware of the Ukraine flag, I'm afraid. The colours do work together and you've created depth with the figures - now lets see a photo of the whole lot together, eh?
Oh and I had pretty much the same problems with red and yellow that you do, until I found Mephiston red and Flash Gitz yellow - for some reason those 2 colours cover very well, even in thin coats (unless they go and change the formula of the paints) - so I use these 2 as my 'default' red and yellow, just going lighter or darker over the top if I want a different shade.