Many thanks for the tips Florian!

There is one thing which is really hard for me to figure out: how do I use the devpiserver_pyramid_configure hook?
The documentation is not that great in the devpi-server experimental hooks section.

My idea is: Create a python package named something like "company-internal-devpi-web-theme".
The package contains python code snippets which are used in customized chameleon templates, all included in the package.
The package could be installed with pip, together with devpi-server and devpi-web. And then the devpi server would be started with the --theme flag.

Perhaps I missed something obvious, but I don't really see where I could inject my own devpiserver_pyramid_configure hook in such scenario.
I don't want to monkeypatch the devpi-web package.

With your previous answers, I was thinking about adding a new view with the route "/{user}/{index}/+inheritance_diagram".
There are currently 112 indices within my company, I was thinking of adding a route "/+orgchart" which would point to a view with the inheritance graph of all indices.
Additionally, I think it would be nice to store some statistics somewhere on the server side to get rid of old and unused indices. People here come and go, and I'm pretty sure that there are "dead" indices that contain packages that have not been used for quite some time. It's not burning, it would be just nice to clean up from time to time. But this is another topic.

Sorry if my questions are silly, but I'm new to web development in general. My lack of knowledge extends to pyramid, chameleon, javascript and all that stuff.
I must say though, that I'm having a lot of fun with that. :-)

Cheers!
Andrzej