cool chapter, though it's difficult to understand its significance without knowing what is Kizaru's power. Light logia is still the most probable theory, but I like it much less now. It would be very cool and meaningfull for an admiral to be taken down and without the strawhats doing it.
From what we've seen if he is Logia (Light) he's just playing around and none of the attacs thrown at him have any point. In support - when he attacks his feet leave a trail just like other logia users do. The bullet that did nothing to him. The cut arm that had no blood.
It gets interesting if he is not logia, but some sort of paramecia. One option for me is the speed fruit or something to that effect. By beeing godly fast he can ride canonballs, his kiks can carry the type of momentum that makes them monstrously destructive and he could possibly be creating the light effects as a sort of effect connected to his ultrafast movement. A speed fruit would also explain why he dals heat damage - due to the friction his body creates when moving ultra fast his feet could be heating up, a la sanji's diable stuff. Lasers could also probably be explained in some semi-scientific way. I like this option since it would mean that his damage will be real, not just the joke it would be if he's a logia.
He could also be a laser laser person. To me that would be very similar to the speed fruit but from another perspective. He could have move as a laser beam on top of that cannon and turned into laser again as it landed. He could really be shooting lasers when he hits explaining the speed and heat damage. He could have burned that bullet with a laser befor it reached his head.
Overall, to me the Logia still makes the most sence as it would explain everything easily and is the simplest explanation (usually the true one), but it would be boooring. Yeah, Light is a cool ebough fruit, but the most fun battles are with some whacky paramecia, not with Logias. I'm really rooting for the Speed fruit as it seems to me the coolest by far and it explains ehis every ability very well, but i can't really figure the lasers if he's Speed and they seem very large part of his style not to be explained.