Do the bounties when they unlock, they throw your level up bar to next level, and try to play the crucibles, they throw up your level as well. 

And if you think the hive is bad, ho man, wait till you see the vex and the Cabal. 

Also you will need back up on the moon's hive levels, So I suggest getting together a fire team so you don't get killed a bunch of times, and you got to fight the Bitches of the hive that will pretty much be easy with the right guns.