Black sleeving does go with everything but I'd not have Just black, black and shade 19 if you want to keep it dark (shade 19 is like a really dark grey, almost black) but it will break up the black a little.
I will see if I can find a sample of the vanilla sands when I'm home next and Il pop it in the post to you. I should have one somewhere.
As for cutting the tubing, I use a really sharp pair of scissors.
It's kinda hard to explain, don't just cut it in 1 motion, cut it, but as you cut rotate the tubing, I always get a straight cut. Also, even if it isn't 100% perfect, as long as it's on the barb fine, and isn't slanted too much you shouldn't have any problems, and it won't be visible once the compression fitting has been put on.