I butcher my own deer and thus have complete control over what I end up with.
Venison is very lean.
If you like more of a game flavor, save some of the fat from the deer if you are making sausage or burger.
I will also abut 10-20% pork shoulder, or loin or add beef suet when grinding.
Otherwise, you cannot make a patty and get it to stay together with venison alone.