I motorized my hand grinder too, when I got tired of cranking. Then I got tired of "trying" to stuff with a grinder so I got an F **** stuffer, that I refurbished. I also added a mixer for big jobs. I typically do 25 to 50 lbs. per session. I am thinking about a smaller stuffer for smaller batches.
Mulepacking, what motor do you have? I see it's a direct connect with love joy couplers but isn't your motor turning too fast? I do not see a speed reducer there at all and that has been my achilles heel. I simply cannot find a speed reducer that will work.