One thing I did not enjoy about the alpha and beta builds was the sense of isolation and loneliness I felt. Usually I only saw 3 or for people in old Russia. Since Destiny is going to be a FPS MMO, I think it should do a better job of living up to the MMO aspect. Each instance and server should be able to have a 77 player capacity. That way I will feel like I am playing with a community and it will make public events feel like a big battle or that I am exploring Bungie's world with an army of guardians.
Bungie already went in on this. They want you to feel like you are one of the few guardians that will save the world. If there are 76 other guardians running side by side through Old Russia, then you wouldn't get this feeling of isolation and extinction that has come to the world.