Yeah, personally the feature I'm looking forward to is materializing "changes" into a document without losing editing history.
At some point your set of changes grows too large or you want to trim it to, say, a few weeks or months. Afaik that isn't possible yet without losing the ability to merging later on.
I'm farmilliar with Automerge, but not its specific features on state compression. In general change set compression is possible with CRDTs but there are some "gotchas" you need to look out for. Most notably, all peers interested in a changeset, have to be completely in sync at the moment of compression, otherwise, depending on which underlying CRDT type you use, there can end up with duplicate entries in for example a Set type. Depending on the use case, 100% peer sync is possible, in others its more challenging.