The relationship chart for Kimikiss is still a mess, but things are getting a little clearer as episode 17 levels up the drama. As Stripey has pointed out it's hard to choose who to root for, knowing that either way a character you like will be heartbroken in the end. Other than the frogs, who I'd love to see boiled and served in some kind of reduction, I really like the whole cast, which makes it hard to pick who to root for.
I'm sure I'll be wrong on most of these, but just for the hell of it, here are some predictions/rambling thoughts on each character (spoilers for through ep 17):
Mao-neechan: While you can argue Mao's been stringing Kai along, I don't think it's fair to slam her for finally realizing who it is she really loves--I think Mao likes Kai well enough, but it's taken time for her to realize it's not the same as the way she feels about Kouichi. I feel bad for Mao because she's in an impossible position--she's finally realized she loves Kouichi, but she knows he's with Yuumi and believes he's happy with her. So what can she do? To put it in RPG-like terms, she has three choices: Do Nothing, Fight (confess), or Run Away. The first one's untenable because it's already causing her a lot of pain, which you can see in her avoiding Kouichi and being down all the time. The second I don't think she'll do either, unless it's in a moment of weakness, because she'll see herself as a nuisance to Kouichi and Yuumi's relationship and she'll want Kouichi to be happy, even if the result is heartbreak for her. So my best guess is she'll pick door number three and get on a plane back to France, and then the big question becomes does Kouichi finally figure out he's the reason she's been acting funny all summer and go after her?
Kai: Kai is the real wildcard in Mao x Kouichi--now that Mao's broken up with him, he can just go on with his life, try to win her back somehow (I'm picturing the scene with John Cusack holding up the boombox playing 'In Your Eyes' for some reason, but that'd be OOC for Kai...), or he can accept defeat and for Mao's sake try to push her to confess to Kouichi. I think Kai's smart enough to figure out that Mao does like Kouichi, the question is if Mao won't confess, will Kai do it for her? I can picture Kai confronting Kouichi, and telling him he's the reason Mao has been down lately--or in reverse, Kouichi could notice Mao is even more depressed than usual, mistakenly think Kai is the cause, and then confront him and have Kai tell Kouichi that way. Kai seems like a good guy, and seems to genuinely like Mao, so I'm thinking knowing he can't make her happy he'll try to push Mao x Kouichi along, but we'll see...
Kouichi: He's probably the biggest mystery--he seems to like Yuumi and clearly had a crush on her from the beginning, but at the same time he worries about Mao a lot, even when he's with Yuumi. Does he really like Mao, but has just put that thought out of his mind, seeing her as unattainable? If he knew Mao liked him, would he stay with Yuumi anyway out of guilt, or apologize to her and go after Mao? Or does he genuinely love Yuumi and Mao's just a childhood friend? I honestly have no clue what Kouichi will do--you can make a really good case either way based on his actions so far.
Yuumi: OK, Yuumi is easy to read--she likes Kouichi, period. That may make her a less interesting character, to me anyway, but she's definitely loyal to Kouichi, so I shouldn't fault her for it. Maybe she'll shock me and go rabu-rabu for the girl with the weird udon fixation, but I don't see Yuumi's feelings changing. Unless Kouichi shows signs of liking Mao, and Yuumi decides to fall on her sword since she's moving away anyway, but that doesn't seem likely.
Kazuki: I'm a little disappointed in Kazuki--Eriko dumped him over the phone, sure, but he doesn't at least go try to confront her in person? Then again, he probably doesn't know where she lives.
Eriko: It's hard to tell what Eriko is thinking, but I'm guessing when she went and saw Kazuki at the soccer match, seeing him celebrating with Asuka just made her feel like her and Kazuki were just too different to be together, and that he'd be happier with Asuka, so she bowed out of the race. I don't believe for a second that she doesn't like Kazuki--the scenes with her and Kazuki at Mitsuki's mansion seemed to pretty conclusively point the other way. Will she realize her true feelings and go after Kazuki? Or will Kazuki try to change her mind once school starts and they see each other again? I'm hoping she does end up with Kazuki--Asuka's a great character too, but Kazuki and Eriko just feel like a better couple to me, even as different as they are.
Asuka: Seeing how depressed Kazuki is will be a big test for Asuka--does she try to reconcile Eriko and Kazuki somehow? Or go the more selfish route, and take advantage of her chance? I don't think she's completely fooled by Eriko's exterior cool, deep down I have to think she believes Eriko does like Kazuki, and it's obvious the reverse is true. I'm guessing she'll fall on her sword and try to help set Eriko and Kazuki back up, believing Kazuki can win her over. In any case, I feel bad for her because it's clear she likes Kazuki and Kazuki only has eyes for Eriko, and most of us have been in her situation at least once in our lives, so it's easy to relate to her.
Mitsuki: Why did her character get introduced again? Is she even still in this show? I can't believe they'd introduce her and set up the whole "arranged marriage vs true love" thing without actually giving her the "true love" part, but she's gotten less screen time than the damn frogs. I was thinking they'd go Mitsuki x Hiiragi maybe, but I've seen zero sign of that so far. Seems like she's been condemned to Minor Side Character Hell, which I guess is fine given how the relationship chart for this series is complicated enough already.
Maybe it's just me, but I can't get used to the new ED--somehow it seems wrong not hearing "koware sou de..." start up at the dramatic moment at the end of each episode...
On an unrelated note--hopefully I'm not jinxing them saying this, but Spice and Wolf and True Tears are just awesome so far. I know as a Kyoani fan it's blasphemy for me to say this, but I'm looking forward to those two every week more than Clannad. I might just buy True Tears even at the insane prices Bandai USA wants to sell it for, provided the ending doesn't go all Mahoromatic Season 2 and turn into a trainwreck or something. Spice and Wolf continues to be impressive too, with Horo one of the more complex, interesting characters I've ever seen anywhere.