One feature worth adding is dot methods completion like goland, some code reference when the REPL is running.
Judging from various posts like Reflections on Developer Experience After Building a Large Julia Codebase - #14 by cuihantao . Autocompletion and function/method discoverability . Allowing the object.method(args...) syntax as an alias for method(object, args ...) - #218 by xgdgsc . The potential user base can be large.