If you have a small budget maybe I would try the stabilizing wheels.

But if you have the budget for it I would get a recumbent trike with more gears. A Terratrike Rover could have 8 gears and be a lot less heavy than your Worksman and still be an easy on and off ride. Or, you can get a delta recumbent that has more gears and also is higher up off the ground than many of the trikes.

Another possibility is a crank forward bike, one that you can put your feet on the ground when you are sitting on the seat. Like an Electra townie or a Trek Pure. Cheaper than the recumbent trikes. But, they are two wheelers so if your balance isn't good once you get going they may not be for you.