As an extension creator I miss information how often they are used, which one is the most popular and which is not used at all. We do not have repo download stats unfortunately and while download stat doesn't give exact number, for sure would provide some useful picture specially when you have no any idea as it is now.
Also, would be good to know the configuration of PC's, localization languages, TC version, Xservers, desktops used and installed extensions.
Let's use a reporting tool which collects such information and sends report to a central site online. This tool may send report automatically when installed, when system started or manually up to the user. Of course report is anonym, do not contain any personal information (well, report delivery mechanism may uncover client IP) and its usage is optional.
For demonstration I wrote a simple program to make such report, see attached file. Client machine is identified with UUID so multiple reports can be assigned to client. It contains info on hardware (CPU, RAM), TC version and configuration, extensions, etc. Of course it can be extended with more info.
http://www.hasix.org/tc/tcprof.txt