I've looked at Kotlin and I liked the design, too. I was just wondering why so many at once. But it would be great if they will replace Groovy at all.

Still I think it's too early to support Kotlin at Enterprise Level. Also I'm in the transition to FP (Functional Programming) and I think Kotlin still misses some functionality around that.

Edit: maybe I will use Kotlin to replace our JavaScript Stack (currently in Angular, but totally against any practice)