Ok, so yes, this show is admittedly "a clusterfuck of elements from popular anime." It has very strong Haruhi vibes coming off of it, and it's bound to have plenty of formulaic Key elements as well. Does this bother me at all, though? Absolutely not. Haruhi and the Key series are among my absolute favorite anime period, and it's nothing new for Key series to have a lot of resemblances to each other. If anything, this is probably the most unique Key story so far!
I watched the first episode live as it aired on TBS via a stream from Japan, but of course I couldn't understand anything. It looked somewhat nice, but it had a lot of talking, and not being able to understand it, this was very boring. Later, I watched it subbed, and enjoyed it quite a bit more (obviously). Reflecting on it now, I think it's grown on me even more since then. Basically, I'm liking this series more and more the more I think about it.
The slapstick comedy is reminiscent of Clannad, certainly, but it was effective enough. TK (C'mon-let's-dance!) might be one of the greatest anime characters of all time (and, "SO DELICIOUS"). The action sequences weren't boring, and they weren't annoying either, which is more than I can say for a lot of anime, and they were pretty to look at, on top of it all. The whole "lolguys, we throw random concerts to distract NPCs when we need to do stuff" element is of course ridiculous and lol-worthy. It's obvious otaku-pandering, but guess what? I don't mind it one bit. This is like sophisticated fanservice, basically. I had thought that Maeda was going to try to outdo Haruhi's famous Live Alive with his own concert scenes, but he definitely hasn't succeeded yet. Cinematographically, he's outdoing K-On, at least, but Haruhi still isn't in his grasp. I think these concert scenes will become a regular part of the plot, though, so I am hoping that he will be able to improve them as the series goes on.
tl;dr, I was looking forward to this series a lot, and I'm liking it more and more the more I see, but it still has room for improvement and needs to come into its own identity.