Helping myself improve at SH

I have been playing .5/1 at various sites for about a month. I have a positive winrate, but only 20k hands, and lately, my performance/decisions make me think I may be running hot. Obviously, I don't have enough hands in PT to be able to search for leaks and correct them. I think my preflop play is solid (24/13- playing somewhat tight to start my SH career), but I feel uncomfortable in lots of postflop situations.

What I'm hoping to achieve by making this post is a few things:
1: Find out how other players in this forum started in SH, how many hands it took them to get comfortable with the playstyle and classify themselves as a long-term winner. I often see players comment that preflop play isn't nearly as important as postflop play (assuming your VPIP and PFR are not insanely high). I would like to improve my postflop play, but I feel I am fine preflop.

2: Determine how to evaluate my play/sessions. Does this just involve posting hands in the forum/looking over HH's in PT? What is your thought process when looking over HH's? Are there any questions you constanly ask yourself?

3: Learning how to play against fish/calling stations (Loose passive players). I know the general idea is to value bet them, but that is about where my understanding ends. On many of the .5/1 tables, it is impossible to get the pot shorthanded with a raise, so I cannot implement many of the strategies I usually see advocated (calling down, value betting, etc.) Does anyone have advice playing against tables full of calling stations? Perhaps wait for a good hand and bet, bet, bet?

Sorry for all the questions/semi-long post, but I'm hoping that we can discuss some of these topics for some of the newer players to the forum.

(Before anyone suggests it, I have read the FAQ, 6-max baby steps, and basically every other "historical" 6-max post.)