Operational crypto enhancements
Subject of managing key material has come up a few times on the lists.
Facility for user can add/drop/mod the controller access token and Tor keys directly to a Tor in boot standby or running mode via controller without requiring disk for them. Some modes of node deployment/use are disposable so in that case config option to autogenerate keys and not write them out to disk, but show them in controller/debug. Allow use of passphrased keys on startup like apache console or via passphrase put in via controller. Disk storage of other bits of .tor may be sensitive enough to keep in core as well.