I haven't reviewed Castle lately because I haven't had time (and if I did have time, I'd much rather review Hawaii Five-0), but I found "Eye of the Beholder" to a pleasant episode worthy of a review.
In general when I watch Castle, I'm bored by the case. The immediate details like how the person die may be interesting, but that quickly descends into lots and lots of expositional dialogue in which the characters say everything that's happening. I don't know about everyone else, but I'd listen to an audiobook if I wanted someone to tell me a story.
"Eye of the Beholder" is far less complicated than previous episodes and didn't have as much dialogue explaining what's going on. Or least the stuff on the side--the Drive reunion of Nathan Fillion and Kristen Lehman--was entertaining enough to push the dialogue away. The episode keeps a fast pace, as Beckett scowls in disapproval and Castle leers continuously.
Bringing up the Beckett and Castle relationship issue is a moot point, but it's something that continues to bother me. It's obvious what the endgame is, but the writers are taking sooooooo long that it doesn't even matter. Beckett has pushed her feelings down so much that she can't even begin to express what she feels in words. It feels like no progress is being made and it's very repetitive by now.