Hi David,
that sounds like a good plan. One thing I'm wondering is where maintenance releases are going to be published, e.g. 3.0.1? Would that override the 3.0 release or would there be a separate p2 repository? It's important that we have a stable p2 repository location for every release to enable consumer to point their builds at a specific release.
Mylyn also produces "integration" builds which is why the drops location exists. This makes is easy to provide multiple builds for a particular release stream. I assume WikiText will only be published to the nightly site and there is no need for integration builds or staging release builds?
Have you thought about how consumers would install WikiText builds into Eclipse? Mylyn provides composite repositories for each Eclipse release stream, e.g.
http://download.eclipse.org/mylyn/releases/neon/ which makes it very simple for users to get the right version for their Eclipse installation.
My suggestion would be to include the appropriate WikiText version in that composite site and assume that Mylyn Docs users will continue to use that as the source for installing WikiText into Eclipse. We can add a step to the WikiText release build to automate updating of those composite sites.