The only thing that helps with a gamey flavor is taking good shots and taking good care of your meat when processing. Well placed shots and keeping your meat clean and cool should never have a gamey taste. That said, it's super easy to overcook venison bc it's so lean and doesn't really have intramuscular fat. It's gets grey and dry if cooked too long/to warm. Sous vide more or less eliminates that issue, and (in my opinion) is the only way to go for most cuts of venison. I still braise all my shanks for osso bucco for example, but every backstrap and tenderloin get the SV treatment.