You start talking with the CAA about a "controllable" device and you're into "Certificate of Airworthiness" declarations. A parachute is simply controlled with 2 controls. "Left' Right" and "Both". Hard Left or right, takes in you into a downward spin which is good for reducing altitude and keeping you close to your opening point. Both controls gives you 'flare' at landing time which slows your impact speed.
I'm sure that the BPA (British Parachute Association) would be willing to assist in arranging a suitable location for landing which is already controlled by 'skydivers in the air'. If not, I'd happily take that liason onbopard if nobody else has a contact with them
According to the CAA regulations, under the weight of 1kg, no issues, simply "up to you" (under the weight of a duck)
Sure it CAN be done, and it can be done relatively cheaply.
Getting control at lower altitude (c.20,000 feet) will be the thing. If a device can go to 100k feet and arrive back at it"s release point, I believe that this has never been done before.
Understanding wind shears at different levels is not a precise science though. I"ve been in freefall and in 60 seconds of descent, have travelled more than 3 miles in the opposite direction to ground winds. (No Fun)