Like what you said, they would not wield weapons, however they would be quick adept at dodging blows, and parrying them with their hands.

The way I see monks is having only one or two punches per round. Their damage comes from their skills. Also, monks would have say 5 stances that they get from level 1. Along the way they would get special skills which when used would do a different thing depending what stance you're in.

An Example, the skill 'Stroayu'.

In the defensive stance;
Stroayu would prepare the Monk for incoming lagging techniques, like bash or trip. When bashed, the Monk would catch and throw the basher, causing them huge pain and perhaps maladicting them.

In the offensive stance
Stroayu would bring the Monk up close for a headbutt, can cause nose bleed, and hurts, a lot.

In the hold stance
Stroayu will cause the Monk to try and slip around behind his target and wraps his arms around their waist. Making the Monk very hard to hit (For the held victem, very easy for other attackers), but also makes it very hard for the held victem to flee. This hold does not hurt the victem.

Then there could be a maladictive stance, and perhaps a throw stance. Each stance would take a round or so lag to switch to, and can be done in and out of combat. Each stance could also have a passive effect or two. Defence = enhanced dodging, or ehanced resist. Whatever, it's just an idea.