The hubstore has its own packaging format, as opposed to standard approach, such as a .whl file with entry_points of setup.py. As a result, you cannot use any of the pre-existing python apps. And if someone makes hubstore-compatible app, it is not going to be usable with regular python tools by default.
The Pyrustic is kinda the same -- it has some cool components, but it also requires a lot of buy-in. I could use better TkInter widgets, but I am not even going to consider it if it requires some sort of interactive, non-scriptable wrapper shell which completely destroys all my existing workflows.
Indeed, Pyrustic is designed in the "all or nothing" fashion because I wanted to make things easier for new Python enthusiasts  and also it's fun to build things from scratch. Then, after my first Show HN, I started to embrace standards: Pyrustic was available exclusively through Github Releases, I then put it on PyPI. Then I moved further away from the standards to offer a packaging/distribution alternative  by taking advantage of Github Releases assets feature and also of the ZIP archive format.
I had planned to implement "requirements.txt" support in Hubstore. Thanks to your feedback I think I can do better. It was fun building solutions from scratch but I'm writing code for humans, I want adoption, so I'm going to do my best to embrace standards even more.
Thanks again for this feedback which I find relevant and useful, I'll be back soon with a version that integrates well with the Python ecosystem, and I'm already looking forward to reading the upcoming HN feedback.