I wouldn't mind if other monsters made appearances in this movie. I would also not mind if either Godzilla or Kong fight any of these monsters before their match. But the battle between Godzilla and Kong should only be between Godzilla and Kong with no other monsters interfering. And I also don't want Godzilla and Kong teaming up against a common enemy. The last thing I want to see is another repeat of Batman Vs Superman. I just want Godzilla and Kong to beat the crap out of each other and at the very end of the movie, the loser (Kong) either retreats or is killed.
And yes, I am hoping and expecting Godzilla to be the clear winner