An I'm also experimenting with cooking venison and grinding it in the food processor. I am however mixing this with BOSS and Cracked corn, but they absolutely love it.
I've had up to 5 or 6 of my ladies free ranging in year round. I used to put commercial feed out for them but once they get a taste of free ranging, they wouldn't touch the commercial feed. That should tell you something about the quality of commercial feed.
The only supplements that I add...