Well they look good from here. Maybe some slight thinning of the far left tube (GPU to rad) but that's being overly picky and could just be the angle of the pic.
If you've got an RGB header I'd go with that. Give you the opportunity to try different colours and pick what you like best - or change your mind. You can probably balance the colours by hand to give the whitest white if that's what you want....or swap it out if you decide white is the way but it isn't bright enough.
I'm becoming a big fan of Aqua Computer's Dr Drop - despite mine leaking
It gives you a good way of checking it's not going to leak before you get stuff wet. For my overkill res, this was really helpful as it needed to be tightened up much tighter than I was expecting before it held the 0.5 bar (8 psi) of test pressure.