The first three episodes have been pretty interesting. It took me a while to properly figure out how all these 18 characters were related to each other, given the all too brief introductions, but I think I've got it now...not that the actual events haven't helped.
Characterization is rough, particularly in terms of background material, but it's hard to demand much right now, given the circumstances and also how the mystery is currently being presented. Battler (now that's a weird name... ) is starting to become a lot more active, which is good, considering how he seemed to be completely underwhelming at first, but beyond a couple of notable scenes he's not too likeable really. Then again, Keiichi (from Higurashi) wasn't exactly a great guy at first either, so I'll give him some space.
Maria's change in behavior seems to be linked to her mother's presence, somehow, to the point that she seems to enjoy the current state of affairs. Eva and Natsuhi had some interesting scenes, but it's hard to say too much about them (or, technically, one of the two...) at the moment. Along the same lines, the George / Shannon subplot just sort of came and went. It made for a good scene, eventually, but I figured that would last longer. I could say more, but you should get the idea. Things are moving at warp speed.
The big question is, naturally, just who or what is Beatrice? There's already an obvious answer, but...it seems way too easy.
I almost wish I had waited until the arc had already ended though, the next week or two will surely increase the tension even more.
Animation quality is entirely average, with a few obvious mistakes. The music seems to be good, I'm even starting to like the ED, at least in context, and the OP is just wonderful. The character designs are alright, not really impressive but not too bad either. Maria's expressions are a bit over the top, that could have been toned down a little (I know, I know), but I would say it works so far.
Despite the initial rush and compression, which is easy to notice even without ever playing the game myself, I've found the story to be fairly intriguing, although we're clearly being intentionally tricked at the moment, in any nuraber of ways. It's probably for the best to wait before getting too carried away with any particular theory, but it's fun to see the show shoot down my speculations every other episode and make me start all over again.
If this is going to be anything like Higurashi, then the later episodes will make up for the early rush and there will be enough exposition eventually. The apparent emphasis on shock isn't everything, I can tell there's potential here so that's not the issue, it's all a matter of execution. For better and for worse, the same people seem to be in charge so we'll have to wait and see.