If I was rich and had plenty of time, I would make some more testing (from darker colour to lighter, etc.). But I will keep testing with that one with Royal blue to see if I can turn it from purple to more blue.
The fun I have with this is whatever the colour it turn out, I can paint over it. So if Rit dye doesn't give me the colour I want, it will make a good chip free base coat and will hopefully reduce the number of Blue coat needed.