i know everyone has their preferences and i kinda want to know what yours is!
While I do some recreational coding in Scheme, for production purposes I now go with Go. Go, IMO, strikes the right valance between simplicity and usability. The language is small enough that you can pick it up in a day. And the standard library has most of what you need for server programming. That's why we use it for Repl.it's infrastructure.
P.s. I moved this question to AMA because it fits better in this board being a question :)
For example there used to be one kind of function now there is arrow function, arrow with body, generators, async, methods, and class constructors. Going from one to six, that is an explosion in complexity.
@JSer you never code in a vacuum, you code with other people and use open-source and once the feature is out then people will use it. Read this post to understand what I mean about functions http://journal.stuffwithstuff.com/2015/02/01/what-color-is-your-function/
I had high hopes for Swift for a while. I think it's a nice language on paper but annoying to work with in practice. XCode has never felt stable to me for very long and using other editors isn't straightforward.
Python 3 - it's easy to use and learn, but not hindered in power because of it.
Java is closely behind, but it's a lot harder to learn and use - not worth the effort in my opinion when Python is around :)