IdeaVim issues

While IdeaVim mostly works well with Cursive, there are some issues. I'm going to use this page to collect a list of problems and get some feedback, and then get in to try to fix some of the issues. Any other issues are welcome below, as well as input on how annoying they are. I don't use IdeaVim (or Vim) myself, so it's very difficult for me to judge the severity of these issues. Similarly, since I'm Vim-illiterate please add some steps to reproduce when describing a problem.

Known problems:

• In IntelliJ, ESC has a very strict meaning when used in toolwindows - it will jump from the toolwindow back to the previous editor. Since Cursive's REPL is in a toolwindow, this means that ESC does not switch modes when in the REPL editor. Note that this does not affect main editors, so if you tend to edit in your main file and then send that to the REPL this is probably not an issue for you. See also #647 for a related problem. (Edit: As of IntelliJ 2019.3, this is now configurable and #647 is obsolete).
• Some of the Cursive keybindings interfere with Vim commands in Normal mode, see #384. This might be a fairly easy problem to fix, if some communication can be added to allow Cursive to determine if IdeaVim is active and in normal mode.
• The IdeaVim commands are not aware of sexp structure, see #1249.

Hints & Tips:

• You can map Cursive actions to some extent using .ideavimrc, see #907 and here. Feedback on how well this works or any problems with it would be great.
• If you can bring yourself to do it, retraining yourself to use Ctrl-[ rather than ESC will generally make your life easier, both in IdeaVim and in other emulators.

Outstanding questions:

Would it be useful to have any sort of specific paredit functionality in Cursive apart from the above for use with IdeaVim?