transmission-cli is in the process of being superceded by the curses client to transmission-daemon. That combo will do what you're suggesting here.
http://github.com/fagga/transmission-remote-cli/tree/master the current location of the curses client. It, or something like it, will be folded into Transmission in an upcoming release. If someone /really/ wants to see this in transmission-cli we'd probably acccept a patch if it's clean, but as far as I'm concerned the curses client is the future and transmission-cli's in a "only bugfixes" phase of maintenance.
