Um, have you tried Monk Of The Four Winds? The Elemental Fist ability is pretty OP. I know that, with the right build, your Halfling will be pretty boss.
If using unchained, a four level rogue dip is very useful if going for a finesse monk. Finesse training unarmed strike + debilitating injury will make a very effective dex based monk / rogue, especially if you go monk of the mantis to keep building up sneak attack dice.