Actually I really like this episode. Certainly better than next week's episode, which gets my vote for worst of the series.
I'll nitpick about one exchange I could have done without:
TROI: Captain, I'm sensing something from the holodeck. It's as if a unifying force or a single consciousness is trying to bring it all into focus.
DATA: There can be only one explanation. In programming Moriarty to defeat me, not Holmes, he had to be able to acquire something which I possess.
PICARD: Exactly what?
DATA: Consciousness, sir. Without it he could not defeat me.
Yeah, like nobody's ever been beaten at a game by an unthinking machine.
It seems unlikely that the Enterprise computer would have the ability to create a consciousness that can be sensed by Troi (who, it should be noted, can not sense Data).
If all we had to evidence Moriarty's consciousness were his own argument, it would invite interesting discussion about what consciousness is, how (or whether) its presence or absence can be assessed from the outside. Unfortunately, the episode has Troi give us all the answers. Moriarty is sentient and Sirus Redblock isn't.