Ultra Dog,

I looked through these forums, including the old data, as a project for Olympia a couple of weeks ago and i didn't find any control options other than the one you listed.  

To control the escort speed, we came up with buying a slower, less horsepower engine for it and increasing armor to get the speed match we wanted.  Apparently the escort will not go into OH so I tinkered with engine selection and armor to get the Yubari I use for escort duties to have a max normal speed of 1 knot faster than max speed of my CV.  It will slowly catch up after I go into OH but isn't fast enough to overrun my CV most of the time.  

Hope this helps.  

Additionally I need to say thank you to you! In doing my reading on any number of topics from subs to CVs (as I'm still relatively "new" at 2 months in,) I've found your posts to be most helpful.   

Those are the 2 ways of "controlling" an escort.
There's a 3rd but it's only open to gun/torpedo ships, and that's your spacebar or the"." to turn the escort off completely...

Only keys are the one you have mentioned.

the ways to control excorts at the moment are:

Turn its firing on and off.

Selecting an engine that makes the base speed of the rental, = or less than the base speed of your current ship.

Sinking or damaging it to limit its speed or completely "turn it off" (There is no EXP penalty for damaging or sinking your own Excort, only if you damage or sink someone elses is there an EXP penalty.