So Construct 3 saves binary blobs that can not be edited externally and are difficult for tracking changes.
While we haven't head anything about how Scirra plans to handle team collaboration, I hope they do have some efficient solution for that. ClickTeam is getting ready to support it, so I don't think it's something Scirra can evade. Again, I'm not implying on that they want to, we still don't know all details.