c’mon folks, narratively we need a low spot before resolving this properly.
the real let-down will be if, post-wake, we don’t see Mizuhara realise how much Kazuya has grown and have some character growth of her own. Go look at Kazuya at the start of this: he’s a loser, he’s a creep and he gets told off for it. This manga is good because he’s not a static harem protagonist, he’s growing into a worthwhile man. He’s not there yet: gotta stop leading the other girls along and all that, but we can at least see why they might find him worth their time.
We could even see Kazuya start to move on and an arc of Mizuhara realising what she’s passed up on. Of course, if they don’t get together at the end it’ll be a betrayal worse than Fuutarou not marrying Itsuki, but narratively speaking Mizuhara moving on from her original goal towards something focussed on what she truly wants and having to work to make Kazuya a part of that would be satisfying. Then again, conventions of the genre mean she doesn’t get to become the point of view character so if it happens it’ll feel rushed: the fast forward finale.