Head shots aren't supposed to be artsy. The showcase is the actor, not the lighting or the composition of the photograph.
While it is an attractive shot on an artistic level, it isn't suitable for a head shot.
For it to be a good head shot...
No shadowing. The face should be well lit.
Hair should be done a little better, and I hope he doesn't plan on changing that look for awhile.
That shirt...looks too sloppy. Casual dress is fine, slovenly is not and that looks more like the later than the former. Great artistically...bad for a head-shot.
He should be more expressive as his lips are very thin. His expression is very bland right here. He needs to play to his attributes which would be his eyes. Corny as it sounds he needs to, "make love" to your camera.
Um, that's about it.