One of the biggest mistakes many people make is when they put a person on a specific hand. That is nearly impossible , instead you should put your opponent on a range of hands and fare that range against yours then procedde with betting, bluffing, raising based on odds, % of times he is likely to fold, call, raise, etc...factoring in his style of play : tag, lag, etc...and *texture of the board*, for example if you get checked raised in position on a rainbow, unconnected flop, you might want to reraise with a stone cold bluff because people usually slow play a big hand ecpecially on a non-dangerous flop , things like that.
Poker has been much more +Ap or +Ev or whatever you want to call it vs bj for me, and you will be surprised at how much oppertunity there is at levels all the way to 5-10 blinds. Reading books don't help that much , instead I advice you of playing loose aggressive style spewing some money off (lower limit) like a maniac for a while, and you will learn so much about patterns, styles, tendencies, etc... way more than books would