Heavy breasts, full of milk, thick nipples, anything that shows this most wonderful part of the female anatomy in all it's milky glory. Milk does not have to be present and breasts do not need to be engorged but they should look like they could feed a few mouths.
Gone Wild 30+ is for women ages 30+ to post nude photos of themselves. Although "30+" is open-ended, in general this is not a subreddit for granny porn. Instead, it's ages thirty-something into forties, and fit fifties.