The first battle occurred on April 19, 1775, the morning after Paul Revere's famous ride.

The Americans lost the Battle of Bunker Hill, but British losses were heavy.

I would have to say the two battles at Saratoga, the battle of White Plains and of course Yorktown. The first two thwarted the 3 point attack of the British to take New York State and to split the colonies into two parts. The radicals who started the war were in New England. The southern colonies just sort of went along with them. The last one was Cornwallis' defeat and the end of the war.

I think that you have to include King's Mountain in this list. The Battle of King's Mountain is what checked the British advance in the South. Had Greene failed there, what would have been the consequence? Obviously this is speculation, but I think that it is reasonable to see the British continuing north. If Cornwallis could have entered Virginia with the South in hand, it is likely that he would have continued. While I do not disagree with your list, I think that it is short one battle.