Thanks for bringing this up! This may actually be a very useful source of information to help us plan further improvements in these areas. I'm still not satisfied with what we have for OS, actually (see this issue)
I'm actually not familiar with this information dictionary. Is there another resource that may help visualize these concepts, other than the 160Mb XML file?
I'll check with a few contributors if they could help us drive this discussion forward.
In the meantime, make sure you check the latest version (ECS 1.3+) of the package schema. I'd like to hear what you have in mind that's missing there, for Windows. Note that at this time, the idea for this field set is specifically around software package distribution systems, such as Chocolatey. It's not currently meant to capture information about software that's installed in different arbitrary ways (installer, zip, etc).