I've mixed Deer with beef, pork, goat, and lamb all with great success. I also did a deer and squirrel chilli, it was prety good. Most other wild meats I've only had on their own.
When people talk about deer tasting gamey, a lot of it has to do with how the deer was killed, how old it is, and how it was processed. You take young deer that was killed cleanly and cleaned and processed correctly there is no gamey taste what so ever. But you shoot an old doe that you have to track for 2 miles, drag it out without feild dressing it. and don't hang it up to drain the blood of course it's going to have an off-gamey flavor.