Luffy beating an Admiral 1 on 1 should be the moment most fans have been waiting for. All this crying is from salty Sanji and Zoro fans who've argued for years which one of them will get Kizaru but in the end he was Luffy's prey.
Don't worry if Luffy doesn't kill him he'll let Zoro has his sloppy seconds after all Zoro is used to that by now
That being said Zoro is 2 or 3 arcs away from being strong enough to contend with an admiral