Check out destroyor's build for a DEX based CRIT PSI MONK (it's in his steam guide). Insane damage, IMHO much preferred to STR, if you are good to go with leather gloves. If you want to use the Power Fist or otherwise prefer a STR route that's doable too, to (I think) at least hard difficulty. The setup is pretty standard for a leather puncher, and things get only a bit more difficult to plan if you go with bare fists or have to think about the trade-off between STR/DEX in a STR build, so I'd rate the DEX build also much more beginner-friendly.