There's probably more you can do without using the mouse than you realize.

> # Change all the 'X's to 'Y's on the current line in 5 seconds.

In PyCharm, I can easily select the current line with Home followed by Shift+End, hit CTRL-R, X, Tab, Y, click Replace All. Doesn't really take much more effort than whatever black magic command vim uses.

> # Syntax highlighting for [any language the IDE doesn't compile].

Then you're using the wrong IDE. PyCharm is primarily a Python IDE, but also does syntax highlighting for JavaScript, HTML, XML, YAML, CSS, and CoffeeScript. Visual Studio Code supports C/C++, C#, CSS, Go HTML, Java, JavaScript, JSON, PHP, Python, and a few others.

Both of them have support for adding custom syntax highlighting.

> # Pipe text through an external program.

I'd be doing this on the command line anyways.

> # Start quickly enough to pop open text files whenever you need it.

I'll give you that one. But that's not enough to do your general development in vim.