I want Luffy to lose to Kaido, because I simply believe we need another Oden.
Oden in my opinion was Roger and Whitebeard's "strongest" crew member, even if it was just temporarily or for a short time. I think World's Strongest Swordsman has a much deeper meaning. Look at the Secret Marine Force, SWORD, the swords on the empty throne and the strongest CoC users use swords.
Luffy can't be everyone. Luffy should only be Roger, Joy Boy and Nika. Zoro and Yamato are the most likely candidates to fill the role of Oden, and obviously my favorite is Zoro. Right now Zoro is pretty much Ryuma, Rayleigh and Oden for me.
The only way I see Luffy beating Kaido, is for Luffy to somehow gain elite swordsmanship using a "Swords" man form like Snake, Tank and Bounce man. Given the silhouette of Nika wielding a sword and spear, I'd think it is possible for Luffy to kill Kaido, but I don't really want Luffy to become a swordsman.
Does gigantic Luffy wielding a giant katana, while using whatever sword mastery to kill or defeat Kaido really make sense? How can Zoro be World's Strongest Swordsman if the Pirate King ends up wielding a sword?