"Militia" had a negative connotation even in the 18th and 19th Centuries. it conveyed an image of untrained, undisciplined wannabes and pretend they ares who were prone to panic, scattered at the first volley from an enemy, wouldn't stand, wouldn't fight outside their home area-the Battle of Queenston Heights in the War of 1812, e.g. During the Civil War the militia in the Confederacy were usually the under- and over-age, led by officers seen as draft dodgers.
Before the Revolution the militiaman was required to provide his own firearm, only requirement was that it could not be of "bastard bore", i.e. anything other than the .75 of the Brown Bess. Though I suspect that wasn't that rigorously enforced.
At the Battle of Cowpens Daniel Morgan put his militia in the front line, his Continentals in the second. He told the militiamen, "Give me two volleys and then you can run." his intent was l they could was slow down, harass the enemy, he didn't expect them to stand.
Excellent point. Morgan knew the militia would run so he used it to his advantage to set a trap. Washington brought in Von Stueben because he knew his men needed proper training. He and his men were getting beaten repeatedly until they became a real army.
Ambush tactics can win some fights on a small scale but that doesn't win the war. Militia can be a real nuisance but real soldiers almost always beat them.