I liked the first episode a lot, and unlike most other anons, I wasn't at all put off when the rest of the show was nothing like the first episode.
I loved the lazy episodes of the three of them doing basically nothing together. After Sara left, I loved the episodes with the two of them trying to cope.
But once the giant squid or whatever the fuck showed up, yeah, it kinda went from sensitive and melancholic to wtf and WTF. It definitely could have ended better.
Also, awesome OP and ED were awesome.