Hrm...
I would expect power bladed staff of intensity to be the best choice for a monk.
http://vg.curse.com/database/items/details/1144881/The problem with powerbladed staff of devestation is that the focusing of power competes with the resonating devestation effects and essentially nerfs the bejesus out of the focusing power raw damage % boost.
By using the intensity proc for resonating instead you get the full effect of the focusing crystals of power which gives a very high raw damage boost to both procs and melee (particularly good for those that persue reasonable amounts of int in their build). The intensity proc is pretty strong as well.
If you are raiding APW of course there are some very nice 1h weapons that a jagged handwrap of striking will complement beutifully. Though you might want to wait a bit until after GU4 for that since currently focusing crystals of pain (adds jagged/crit% boost) and resonating crystals of striking (boosts raw damage stats on weapon plus procs striking) are both DAMN expensive.
After GU4 most crystals in general "should" be a little easier to come by.
A weird combo that I've considered is using a high int build and using the appropriate specialized upgraded spell damage focus in my offhand...consider that you still essentially do "weaponless" offhand damage if you have a focus equipped, so its like having an offhand weapon equipped that does your basic barehand damage but boosts your secret of choice (fire/etc.)
I've been thinking with a high enough int build, its possible that a specified spell damage focus will provide more net damage boost than a standard offhand weapon. This is TOTAL speculation, I haven't messed around with this or parsed a damn thing. I figure your basic offhand (unless you have access to something VERY powerful is about 25% better than your "weaponless" offhand, but that is cut in half since its offhand. So an upgraded specified sdfocus would boost secrets of that type by about 15% and that boost is not reduced by being held in offhand. I can also be made to grant 150hps or 19int or a few other options.
Considering how dirt cheap the mats are to make a flawless spelldamage focus it might not be a silly way to start out until someone gets a hold of two very solid 1h weapons or an ideal 2hander. Ignoring that...it just seems like a fun concept.

The basic upgraded specified type is like this:
http://vg.curse.com/database/items/details/1269575/So this example would only work with secret of fire, you would need other specified types for other secrets...but that's easy enough to build in a marco to just switch your sdfocus when you switch to a diff secret type.
Totally off the typical beaten path I know but something I was thinking about.
