Having used Scala I can't stand to go back to Python. Almost as lightweight (more lightweight in some places - case classes and "_ lambdas" are things I really missed in Python, though attrs maybe solves the first), but a whole lot safer, which makes it much easier to refactor, which makes it possible to maintain a much higher quality standard in a long-lived codebase.
And the whole library/build ecosystem works a lot better - partly the problem is harder for Python because many "python" libraries rely on native code (whereas JNI is relatively rare), but it seems there are still four or five different ways to build and package Python projects and to work at an organization with a large Python codebase you end up having to understand all of them. (Every few years I see a blog post on how the packaging problem is totally solved now, for real this time, but at this point I've stopped believing them).
And the whole library/build ecosystem works a lot better - partly the problem is harder for Python because many "python" libraries rely on native code (whereas JNI is relatively rare), but it seems there are still four or five different ways to build and package Python projects and to work at an organization with a large Python codebase you end up having to understand all of them. (Every few years I see a blog post on how the packaging problem is totally solved now, for real this time, but at this point I've stopped believing them).