Working on a simple desktop-based PICO-8 IDE for Windows/Linux/MacOS. Features: syntax highlighting, code overview, reads/writes the P8 file format, copy/paste sprites directly to system clipboard for easy interop, large map editor.

What other features would you enjoy in a desktop IDE?

(same as my tweet comment)
I would not bother starting a new editor given the infinite set of features already available in pick your favorite editor but rather a plugin to an existing one.