Visually I like Kayn blue more but I know that the red Kayn is more useful, and I also think it is more broken because it has life steal, but the blue also has something that feels better in other situations.
Cheer up, the good thing is that in defeats there are always things from which we can learn.
Best regards.
I also find the Blue Kayn much better visually than the Red, lately I've been using this variation of Darkin from time to time, it seems to me that its healing isn't as efficient for an End Game combat.