I feel your pain OP, but luckily, mine was gift. I sometimes feel bad because my parents mainly see me gaming on my PS3, so I just turn on the PS4 for Netflix. I agree with you on the UI; it's a mess and a little time consuming to find stuff you're looking for, and I also don't like that it displays your name instead of your PSN ID on the what's new/social section. Don't really mind the social stuff, but I would like a notification of when someone signs in if Sony is pushing the social thing.
I do, however, like that you can download/install games while watching Netflix and even while playing games. The downloads pause on the PS3 while you're on Netflix. Also like that the PSN store isn't a sluggish mess unlike the PS3's.
As for the library, there's not really much that interests me; the only games that do interest me are PS3 games. Hoping that Final Fantasy and Batman can provided me with some PS4 gaming, but as of right now, I'm not really impressed.