Free: Contests & Raffles.
As long as your anchor point is consistent, thats what matters! Everytime, the exact same way.
The nose is important to keep your head anchored the same way every time. Is it mandatory? No, but it will make a difference in accuracy especially at distance. At this point you would probably have to make a peep adjustment to start anchoring your nose on your string. If it were me I would make the adjustment.