I haven't gone hunting yet in Massachusetts with a muzzleloader (just with bow and arrow), but some of the laws oriented around carrying certain firearms in the woods while hunting seasons are in effect are difficult to understand, so from a legal standpoint you are just better off leaving the handgun at home.
Our only "big predator" here is coyote (there are some bears, as well as unofficial sightings of wolves and mountain lions, but they are fairly rare and largely limited to the mountainous western half of the state), so i am not too concerned about throwing down with something that wants to nibble on my toes. In the future, I might get a ML hangun to match my musket, but that is as much for cool-factor as it is for actual utility