Finally got around to watching the rest of Seitokai no Ichizon - and damn, that was a mess.
Now, don't get me wrong - I liked it just enough, as a comedy it's quite decent, and the girls are quite likable. But... It tries to incorporate serious motives, and fails miserably. It seems to be pretty meta at first - what with the aiming for the harem ending, eroge talk and all that. But it's just a thin decorative layer - despite the characters being aware of them, the common tropes are played ridiculously straight. Compare that to, say, Genshiken, which has a somewhat similar(albeit taken further) premise, but with much better developed personalities and relationships between the characters.
Then there's the backstory - sure, there's just enough of it to piece most of the things together(other then one thing, how exactly the girls Sugisaki was two-timing are happy now), but it's treatment is way too shallow, and it feels like a forced way to introduce the things that series seemingly made fun of as actual plot elements. Did it need to treat them seriously? At least for what was shown in the anime, definitely no.
The matter of the ending - it was okay, but only because I didn't expect any more(well, Mafuyu's throwaway confession was a bit of a bummer). But if one were to treat the backstory seriously, it would certainly seem lacking. I doubt we're going to see a second season - but OVAs are quite likely. Not to mention the series works perfectly as a commercial for the light novels.
All in all it seems like the author wanted to write a satire/subversion of the harem genre - but got stuck in the exact same patterns he was supposed to parody.