Preaching what I like, and I'm not into extreme performance much:
- Ruby for most things (most generalist language I know)
- JS for whatever can't be done in Ruby
- Other languages when anything really can't be done (or a magnitude harder) in JS or Ruby
I think just trying out to make some simple thing (e.g. an Hacker News scrapper) in different languages will tell you much more than any person's opinions.
https://learnxinyminutes.com helps grabs the basics of a language quickly (especially as you are familiar with other languages).
OP said he already works with Python most of the time, so even if I live Ruby as the next guy, it's not a good recommendation.
I would say try Elixir since trying to go and think only functional for a while can be refreshing and useful also when you come back to the languages you already work with.
- Ruby for most things (most generalist language I know)
- JS for whatever can't be done in Ruby
- Other languages when anything really can't be done (or a magnitude harder) in JS or Ruby
I think just trying out to make some simple thing (e.g. an Hacker News scrapper) in different languages will tell you much more than any person's opinions.
https://learnxinyminutes.com helps grabs the basics of a language quickly (especially as you are familiar with other languages).