I agree that in terms of content there isn't much more to tell other than the relationship between the two leads. If what you guys are saying is true and the anime really did cover most of the LN, making a second season would be extremely dangerous. If there isn't much canon left to cover, I believe the anime should be left as it is with the appreciation I have for it right now.
And judging from when I went and had a look at some of the reviews on Amazon Japan, which were mostly one star, it seems that they pissed off a lot of Sakurasou fans hugely just by changing a single scene in one of the early episodes, so I think they'll be hesitant to make a new season which is mostly original content.
The Amazon comments are pretty much all referring to the Korean dish they put in the anime in episode 6 (instead of a Japanese dish in the LN). Japanese (otaku) are very nationalistic, so anything Korean in their anime gets an instant downvote.
I was under the impression that the scene with the korean food had replaced a bath scene in the books, and that's what they were angry about. Though yeah, knowing the Japanese, it's quite probable that a good chunk of them were angry because it was Korean, and not because they'd missed out on some fanservice.
A similar thing happened in
Hentai Ouji to Warawanai Neko as well, though to a smaller extent.
In episode 4 of that show, during the train scene with Youto, there's a brief instance of a poster advertising a Korean pop idol in the background. I think it's a blink-and-you'll-miss-it moment, but the Japanese otaku are very, VERY observant, so it didn't take long for this to become public.
Now, the director promised it would be removed on the Blu-Rays and it likely won't hinder that show's sales too much, but I took a gander at some negative comments on Amazon Japan and with the help of Google Translate, one thing kept popping up:
Korea, meaning that this one, insignificant detail got blown way out of proportion and might discourage newcomers (aka, those who haven't seen the show on TV) from trying it out.
This goes to show you how deep resentment towards Korea goes in Japan (or at the very least, Japanese otaku). Now, if that little detail was enough to have them frothing at the mouth, imagine what changing that one thing in
Sakurasou (whether it's a bath scene or a mere change of food) might have done to them, especially since the studio
didn't cover that up.