newt
Repo tool only solved problem of downloading addons, but it could not install multiple addons. Now user only could add addons one by one manually.
Well it wouldn't be especially hard to make a web based repository that could bundle multiple plugs, or behaviors together.
That would work out fairly well for C2, but yeah, not for C3.
Maybe if Scirra made some addition to allow the user to point his, or her editor at the url of a repo.
Github would make a lot of sense here.