I prefer console in general, for everything. I've been doing this for 20+ years, and you can pry it from my cold, dead hands.
The base editor is open source but you can get the full PyCharm for $99 per year. Worth every cent.
The only thing I've found PyCharm good for is doing other functions, like linting, not for the actual code editing. No IDE is any good for that. Luckily, PyCharm works just fine when the code it's working with changes on the filesystem below it because of the use of an external editor.
I've never found I needed to use a GUI for developing software, outside of a browser.
To be fair, most other mainstream languages (except maybe Go) lack that kind of tooling too, but at least their cultures do not encourage liberal use of deeply nested directory trees and overengineered abstractions, the way Java does.
With respect to vim, at the primitive end of the spectrum is ctags. At the opposite end there are things like the fabulous vim-go, which provides all the functionality that you'd expect in a traditional IDE. There are many similar plugins for other languages.
Regardless, I contest the idea that you have to use an IDE. I find traditional UNIX tools more than sufficient for programming in any language. I can find definitions with grep, use ctags and vim's chugger to manage definitions across many files in many directories. I'm also not limited to the scope of just one project. The tools I use and my expertise with them can then be applied to any language or problem. I use the same tools to write emails and commit messages.
Large legacy Java programs may be frustrating, but they're not all that bad, and certainly don't warrant requiring maintainers to learn and use an IDE.