[ICWiener]

My own point of view is biased, admittedly, but I couldn't stop thinking that Common Lisp was relevant for each item in your list.

Of course, much isn't built-in, but this is not as bad as it sounds: concurrent channels are not part of the language specification, but you can install the "calispel" or "cl-actors" libraries that gives you what looks like primitive constructs.

Regarding "modern" languages, I like this quote from the author of pgloader: "I switched from Python to Lisp because I wanted a modern language" (also transcribed as: "[...] in searching for a modern programming language the best candidate I found was actually Common Lisp."; see http://tapoueh.org/blog/2014/05/14-pgloader-got-faster.html)