Quoted from MikeO:What I heard was Gottlieb's rule of thumb for a proper set up was that a player should win one game for every two games paid for. That was the balance that made the games appealing enough to keep you coming back without making it too easy.
I've heard this about the amount of games won/paid for, I have to say that I don't think I ever get close to that ratio (including matches!). Thankfully they are all 'free' at home.
In regards to liberal vs. conservative post settings, it is certainly something that is easy enough to try it each way. I usually set side drains to liberal to increase length of ball time if nothing else.