I love Deflect Missiles. Spend one die: deflect a missile. Spend another die: catch the missile. Spend another die: throw it back at the attacker.
I'm actually starting to like the idea of Expertise as something lots of classes can use, as long as they all use it in different ways. I think the only problem with the Rogue using expertise was that the way he used it was too similar to the way the Fighter used it. As we can see, the Monk with expertise dice still feels like a Monk.
See, I'm not sure I agree here, especially with that last part.
The monk-only maneuvers are very cool, and hopefully indicative of where they're going with maneuvers in general (extra benefits for spending more dice). But the monk doesn't even get to choose a maneuver (or ANY other class feature) until 4th level, which is unique (in a bad way) among the current playtest classes. Meanwhile, he's got Ki powers tacked on there, which could be cool except that he can only use it for the bleh Stunning Strike until fifth level, when it becomes a nice self-heal.
IMHO, Wholeness of Body and Stunning Strike could both be turned into maneuvers fairly easily. Make Wholeness of Body expend an HD (and maybe give the monk a bonus HD or two) and make Stunning Strike just a normal maneuver, maybe DC=10+(your highest expertise die roll).
Or alternately, you could give the monk a bunch more ki points and have him spend them instead of expertise dice, so the monk becomes a daily-power melee class.
But having both systems in there side by side, in this current iteration at least, seems clunky.
Basically, by having two different power-delivery systems side by side, the flexibility of the class is limited. "Monk" is a very broad class concept just begging for further subdivision: monastic schools focusing in mystic arts, in raw physical endurance, in wire-fu mobility, and so on. By tying monks into the apparently universal expertise mechanic, the possibilities are limited.