? about DIY ground meat

Anyone who home grinds  beef/pork/poultry, any suggestions on fat ratios (right now I do 80/20)and suggestion for adding fat to poultry without changing the flavor ? AT this point I don't add anything to poultry and no idea what could be added to bump up the fat content.

I'm not finding much info on doing a home grind for a keto diet, hoping someone around here has some  tips or can direct me to some place w/info.

(Hoping maybe there's a Butcher on board here at CM)