As we all know Destiny is most likely most fun with a friend. Although I know that I will sink in more hours into Destiny than some of my friends and vice versa. What I think should happen is there should be a limitation on what enemies spawn based on how low the lowest level player is in your group. So if you're level 15 the highest level enemy should be 15 not 25 or 30. Also these enemies should do more damage to me based on my level and less to my friend. I'm not sure how they will implement this with attacks that have splash damage though.
One other thing is I hope these missions with your friends are just side missions and not main quests. I can't tell you how many games have dumbed down the story just so you can have your friend beside you in combat. I don't want that in Destiny. Let me know what you guys think below.
-
I'm thinking that your level will not greatly impact your ability to deal damage.