As far as ring games go,I am stricly a limit player,and make a decent profit from playing limit ring games.
I usually like my BR to maintain around 500 BB.
I play 6/12 or 8/16 minimum.
Sometimes "very occasionally,only super soft seat" I will play a 4/8.
I believe you must play at least 4/8 to beat the rake.
Anythnig less and you are playing an eventual loser game.
Thats just my honest opinion.
But I do like to keep my BR at 500 BB when possible.
They say 300 is fine,but 500 gives you some comfort room.