I am completing current projects which began in a different language, and changing now is not an option.
I am strongly considering using Ada, in particular the SPARK 2014 dialect, because I am interested in provably correct software. After that I am impressed by Eiffel's Design-By-Contract, which is essentially what SPARK 2014 uses; SCOOP; and void-safety. I am not aware of those latter two being so well-handled in any other language. (Kotlin does nicely with void-safety, but according to the Eiffel mailing list Kotlin's developers admit they don't have it down pat.) Nim has some great features, and I love the efficiency, but a lot of the safety aspects are still being worked out, including some fairly fundamental features such as pointers and in particular pointer safety. So it's in the mix, and I dabble with it for time to time, but it's not my top choice for my next project.
