If you are looking to improve what you have I would keep the one with the better comb. Getting the comb right has always been one of the hardest things for me to do , know matter what breed I have been working with. Out of all of the Giants I have , not one has a good 6 point comb.
I would then try to find pullets or hens with good lacing to breed to the back to the one with the good comb. I have found getting feathering and body style right is easier than the comb.
Also, you probably already know this but, judges like this breed to look like a round ball, almost no back.