Season 1 I liked a lot. Season 2 has lost a lot of charm. I watched it and I even enjoyed sometimes, but it's less fun than the first season.
The show's engine is the Uzaki-Sakurai relationship. Uzaki is short, buxom and tends to ride roughshod over Sakurai's protests, but she's lovable. She's also great fun! She's determined to drag Sakurai out of his grumpy sarcastic loner shell, which is exactly what he'd needed to rescue him from what might have become a life of solitude. He's as rude as she is, incidentally, but it's a different kind of rudeness. He's fair-minded, serious and only obnoxious when provoked.
The good news is that the show's not just trying to recycle past glories. It's moving on. It's got character development, especially for Sakurai. This season is much more explicitly a romantic comedy, with the final episode especially being built on "will they or won't they". However:
(a) it's not that good at romantic comedy. We spend surprisingly little time hanging out with just Uzaki and Sakurai, with the rest of the cast cluttering up the place and drawing away screen time. Furthermore, the more explicit romantic narrative trajectory is liable to make what Uzaki-Sakurai scenes we do get a bit annoying. (Although I do still like them both.)
(b) the busybody characters (Ami Asai and Itsuhito Sakaki) are way past their sell-by date. They've projected all their dramatic motivation on to Uzaki and Sakurai. They're basically just talking scenery that won't shut up or go away. Before long, I was groaning when they appeared.
(c) Uzaki's family saves the season. I'd been close to abandoning it when they appeared almost halfway through. I like them all, especially Dad, although Mum's persistent misunderstandings about Sakurai's motivations can get a bit old. Unfortunately, the writer knows how good they are and does a jarring 180-degree turn. After 16 episodes in which Uzaki's home was almost empty (bar Mum), suddenly Mum, Dad, Yanagi and Kiri are everywhere you look. I like them and they saved the show, but... what? Come on, really.
(d) Kuso Cat. I'd hated it in Season 1 too, but here the anti-gag's been dragged still further (and lower). The show clearly inserted it for the sake of "comedy" reactions to Uzaki and Sakurai's antics when there aren't any other humans around, but it's a reality-breaking mistake and it would be possible to have a fairly long rant about this show's idea of tsukkomi and comedy reactions. (See also the busybodies and their rice-eating, which can sod off and die.)
It's a mixed bag. Some episodes just felt clumsy, as if the show had lost its touch and was throwing weak ideas at us without understanding what had been good about Season 1. There's the odd implausible coincidence, e.g. Sakurai showing up in ep.9. Fortunately, though, it can still be fun. The families save it. We meet Sakurai's family too and... yeah, he's got it tough. His dad's a scumbag. The season's family focus was capable of reminding me of The Simpsons (which was ostensibly about Bart, but is really about Homer).
Having finished it... well, I still like the show as a whole. Season 2 has a reasonable ending. I liked the non-busybodies and I wanted the best for our idiot heroes. (And, yes, their IQs have fallen from the already middling levels of Season 1. In ep.12, for instance, Sakurai and Fujio hatch a plan to keep secrets by getting drunk off your arse. Spot the flaw.) I'll keep the episodes and one day I'll marathon the whole show, to see if the dividing line between the seasons is as stark as I've been implying here. It probably isn't and I'm sure the memory cheats, but I've described my current impressions here.
Season 1 = recommended and I love it.
Season 2 = sometimes it's okay, but feel free to skip the annoying episodes. It wouldn't be absurd to jump in at ep.5 with the introduction of Uzaki's family.