I like the implication that we can have an alternative to uv speed-wise, but I think reliability and understandability are more important in this context (so this comment is a bit off-topic).

What I want from a package manager is that it just works.

That's what I mostly like about uv.

Many of the changes that made speed possible were to reduce the complexity and thus the likelihood of things not working.

What I don't like about uv (or pip or many other package managers), is that the programmer isn't given a clear mental model of what's happening and thus how to fix the inevitable problems. Better (pubhub) error messages are good, but it's rare that they can provide specific fixes. So even if you get 99% speed, you end up with 1% perplexity and diagnostic black boxes.

To me the time that matters most is time to fix problems that arise.