Hi Jeremy, Yes I would consider using your suggestion…If I understand correctly when using mode controller I would not be able able to command to any position but only to predefined positions(presets). Is it not possible to use both range controller and mode controller in a group definition?
With the mode controller I would then define preset positions and STOP would work but using Alexa routine. How would MOVE work? Which direction would it move, UP/DOWN? I quickly tried mode controller but the item was not discovered. After your reply I now know why… Rollershutter type is not supported.
The binding I am using is BTicino/OpenWebNet for BUS controlled blinds, lights, thermostats, switches and much more. It is currently and actively being developed further. As I am not an expert I asked the developer @massi et al to take a look over here. Maybe you guys could work together and be more effective than getting ideas from lesser mortals like me 
I hope that is OK with you.