Most of the commands look fine at first glance, although I suspect different ideas would appear when (and only when) it actually get implemented and used in the wild. One particular part I don’t really understand is inspect though; I didn’t see it mentioned up-thread, and there’s no explanation on what it does.
Also, linking back to When you kick the packaging hornet's nest on Twitter, the hornets seem to want an opinionated, KISS solution, there are some concerns (mine included) to implement the Platypus in pip. There are multiple reasons, including 1. the current design and implementation deviates too much from the proposal, and 2. most pip contributors do not want it to fit the proposed role.
Edit: This thread also kind of overlaps with Developing a single tool for building/developing projects (which is split from the Twitter hornet nest thread).