Yeah, the same inheritance is what caused the problems with the SyncedModel subclasses in main (e.g. VideoLog).  I'm on the fence here about being explicit / consistent, vs. eliminating from subclasses of SyncedModel.  Another option would be to have a dummy model SecureSyncModel which simply sets Meta, then have everything inherit from that.

I'm not convinced any solution is better than any other, so if you have a preference, let me know!