Most Giant breeders do weigh their birds, and at shows 90% fall within the range for the Breed (Non Hatchery birds). While a lot of Breeders would love to get their hands on a 16-17 pound cock bird, that bird does not fall within the standard for the breed, and is at as big a fault as an...
A few more pictures would help. Standing with head up not moving.
At that age don't worry about weight, look for type and frame. Long and wide, flat back deep keel. Traits like number of points on the comb are secondary to type. If you are looking for a good starting point, Type first. Now...
A few pointers that might help. Get a digital high/low thermometer. That way you will know exactly the range that your eggs are being cooked with. I have an LG that I use for hatching, and it varies greatly. The three to five days of hatching don't seem to cook them like with the full 21 days...
It is the little plastic arm that goes between the rocker and the motor, I think it is like 6 or 7 dollars. Have the incubator on its top, open, with eggs broken is the larger concern.