I've used Python, Qt and BeeWare to develop an interactive tool to analyse compressed video. It's fast enough that I don't know it's not a native app. You can make some very complex applications if you learn to take advantage Qt's features.

I start with a release of WinPython, then use its command line to make a virtual environment, install `briefcase` and go from there.

I should also add that I found FMan's Build System to be quite easy to do the same thing: https://github.com/mherrmann/fbs-tutorial