I stack skill speed and I have 0 TP issues. You need to manage your TP very strictly if you are going for skill speed stack build. I like it. A lot don't. Crit is fine, but in my opinion monks get too much free crit from IR, BS, and TS that I find it redundant to stack. The skill speed has more uses as once you hit the 491 gate, you can start using true strike again without losing your twin snakes buff.