Each language have its strengths, and what you seem to enjoy is real time evaluation, so compiled languages are not a real option.
On the same point, languages with a REPL might be fun for you, I could think of:
Those 2 languages are the trend recently but also still quite a niche.
(I understand those are not JS nor Python, but I think bringing those to your attention could help you broaden your selection...)
Why do I propose them? Because they are fun and will teach you some good practice and some of programming heritage (Lisp dialect with Clojure, Functional Programming with Elixir).
They also have a nice eco-system so you'll have all the tools you need.
Personally, I use both for small projects:
Those are just my 2 cents. A lot of other languages have potential as well.