The problem with languages is they don't compose. Iow, one missing feature needed automatically invalidates the language entirely. Swift is targeted at Apple platforms and cross platform is an after thought. Kotlin targets JVM and while it is cool in concept, I hate it as a user (and Kotlin native isn't near as mature). If were considering something else at this stage I'd probably put my time into F#, but even it has its cons.
NOTE: By "compose" I mean that if I want feature A, B and C from lang X (has A and B), Y (has B and C) and Z (has A and C), but there is no way to get A, B and C in one language without creating a brand new one. I cannot mix and match features from different languages.
