I use chocolate melts coloured with either powder or gel colour and some copha added (to thin it out - also helps to give it a nice 'crack').
I never thought to colour white choc with gel, great tip.
I agree with PP, i have always had success with the Wilton candy melts. Not sure how the choc melts would go.
PP, i have made cake pops with White wings choc packet mix "our most popular mix', 4 dessertspoons or so of Betty crocker choc frosting.
Bake cake, cool, crumble, add frosting, roll into balls, refrigerate overnight to firm. Melt some candy, take 10 balls out of fridge at a time and dip end of stick in candy then in to ball. Refrigerate again, whilst do 10 more and so on. (makes approx 50)
Then once all sticks done, melt more candy, dip balls in candy, place in to foam block to set. I cover the blocks in colours of the party.
I don't put them back in the fridge, they are fine in a cool room until party a day or two later. They stay moist for days and have a mudcake kind of taste.
I have also made red velvet cake pops, with vanilla frosting, coated with white candy, and red and green choc chips on top, for Christmas.