That is a very daunting amount of models to paint! You are a far braver man than me!
For the color, you can maybe spot I did some test with red and blue, but some friend said it did not really fit. Wich I do think so a bit aswell. Yet I can't say my current color scheme makes me happy so I will try a few things for a while until I do find what color I want to have. And then it's going to be building and painting time!!!
I think red and blue together in a scheme can work...but it's difficult. As they are both bold, primary colours, they will fight for attention (Part of the reason I hate my Eldar at the moment...too much red, which makes the models fight themselves). If you only have one of the colours acting as the focus, with the other as a spot colour, used in strict moderation, it can work...but balance is key.
Whatever you end up deciding, good luck!