I also have an Avon
"Roll-up" 11.5 ft inflatable dinghy
in a carrying bag. It is about 10 years old but still worked when I used it 5 years ago.
However, hanging a 30HP outboard
on anything other than a "Rigid" dinghy
might be rather dangerous both from a weight standpoint and a power standpoint.
The inflatable dinghy has a tendency to "ripple" or buckle (form a buckle in the floor that raises) as the speed is increased from idle to planning speed. It is quite dramatic until you get used to it. And once the dinghy is out of the water
up on plane - with such a powerful motor
there is also the heightened risk of flipping end over end as wind
forces it way between the boat
and the surface of the water
Most inflatable dinghies I know of are limited to not more than 10HP because of these problems. They are just not rigid enough.