Why would we have more reasonable arguments? Kimmimaro is no closer to kaguya than any other character is. Just because his clan has the same name as her doesn't mean he has a strong connection to her. That's like saying the hogoromo clan is very close to hogoromo himself.
Him abandoning Orochimaru is too OOC imo.
Kimimaro probably wouldn't abandon Orochimaru for Akatsuki, considering how Orochimaru considered them the greatest threat to his plans back in early part two. It would've been cool if he lived, though.
Would've been cool to see kimi as oros vessel.
Why would we have more reasonable arguments? Kimmimaro is no closer to kaguya than any other character is. Just because his clan has the same name as her doesn't mean he has a strong connection to her. That's like saying the hogoromo clan is very close to hogoromo himself.
He has her KKG +Curse Mark/Senjutsu.. If that's not close to you then I don't know what is :|
That's not enough, uchiha, senju, hyuga and many others share such traits why specifically kimmimaro? I can understand his connection to her but BZ, madara and her other direct descendants possess much greater connections. I don't see how having him want to revive kaguya being anymore reasonable than BZ wanting to revive her