I'm certainly not trying to ruffle any feathers here, but in my humble opinion the best remedy for antler growth is breeding with line-bred deer for the look that you want to achieve. Then take the time to study and match that up with your does to increase your odds of creating the type of animal that you desire.
I'm sorry, but breeding "name" A with "name" B because they are both "popular" is NOT a recipe for success. Take some time to study genetics in general and pass down traits in whitetails. Then do some more homework and try to weed out all of the negative traits... these are the basics of "breeding". I'm not an expert by any means, and I don't claim to be, but there's a lot to be gained from doing your homework when it comes to breeding deer.
Our feed mix couldn't be any more generic or simple. We don't feed anything that isn't 100% natural. Feed additives/supplements may get you some extra "funky" inches of antler growth, but if you really want to grow huge deer the answer is simple... GENETICS!
Just my 0.2 cents.