Washington disliked rifle units and tried to disband them during the war.
Washington came to realize that riflemen unsupported by musket and bayonet armed regular infantry were at a great disadvantage against the British regulars.
He didn't want more than 1,000 with the army at any one time. The rifles were not of a uniform caliber, were slow to load, and could not be fitted with a bayonet.
He did approve of the organization of the provisional unit commanded by Morgan in 1777 and sent it to the Northern Department for employment against Burgoyne.
After Morgan's unit returned to the main army the unit was broken up and was never reactivated. Rifle units, either militia or state troops, were used effectively with Greene's southern army and were usually brigaded, as at Guilford Courthouse, with regular Continental infantry.
In the northern battles, Morgan's riflemen were brigaded with a provisional light infantry unit commanded by Henry Dearborn and the two worked together successfully.
Gorham's Rangers, commanded by the Gorham brothers, were veterans working long before Rogers learned to shave.
The Queen's Rangers did not become an effective unit under Rogers, but did after first Wemyss, and then Simcoe (both British officers), became their commanders.