You are forgetting the govm't was King George and the boys. After the war Congress established arsenals... ect to scale with their new condition. THey did not replace private sources, or eliminate private holdings. Not until FDR did the US start to disarm their citizens. Until that time all manner of arms were available.
"artillery not stored in private homes nor owned by private individuals or groups."
No one stores cannons in their home. They go in the workshop. The gun owners shop.
"Artillery was extremely unwieldy and hard to move especially if the weather had any wetness...
Yea, mud. I'm well aware of moving and shooting cannons. I've done it under the same conditions. With imaginary opponents of course.
"Hamilton"
Officers train juniors, that train sgts, that train crews. Once in the field it's the sgts gun and the shooting is directed by the officer in charge, but done by the sgts and their crews.