I've got a 30mm red dot with a 3moa dot that I have switched around to several different guns. I too would recommend staying with a small dot so as not to cover up the whole critter, I zero mine for point of impact at the top center of the dot at 50 yds when on a .22 for rabbits and squirrels, put the red dot right below the bunnies eye and out go the lights.
bergie