Well... there ARE certain indicators that an Ayase ending is completely impossible. I strongly doubt that it will end this way for other non-Ayase-related reasons, but her relationship with Kyousuke is at least not beyond mending.
Yes, she insists that she "hates" him (though clearly not with the bite of old), but there are multiple indications that she's thawing: After all, she admitted that in the beginning she "liked him a bit", and that he now "seems to be a kind guy" that she "would feel like being friends with". If he weren't such a pervert that she'd hate
Another example: When Kyousuke asked if she'd be his girlfriend now if they wouldn't have had the well-known falling-out, she answered (literally) "With the current situation, there's no way I'll be able to date you". Note the very peculiar wording. She doesn't shoot him down or ridicules his repeated advances, even though she easily could have (and what would be no uncommon reaction from model-level girls who are used to fending off unwanted attention). Taken at face value, she effectively implies that should the situation change, it might be different.
This is why I'd love an Ayase path. Because the motif of "guy works on girl till she overcomes her hatred" could be really interesting and fun, especially with a character as playful-spirited as her.
Ah well. I guess it will have to wait for summaries from those JP-skilled people who can read/play it firsthand.