These sound like some interesting and good ideas, I had a couple questions about them.

If there was a tabbed seperation between core services and third party services, where would you include things like a SQL Server, Exchange, or BizTalk service?

You also mentioned having a need to create some windows services, would you mind describing what you've needed to create them for?

Also, I think I remember seeing a uility in the resource kit you might be able to use to manually uninstall services entries without having to use Regedit directly.