After having got my brother a PS4 for Christmas, he bought me Destiny and I've surprisingly gotten pretty addicted to this game so far and really enjoying it. Llaying a Sunsinger Warlock and just hit level 20 today, with 2 pieces of gear i got boasting me up to Light 22 (I think they came from me buying the Season pass?) So what do I do now that I'm at this point? Just tried a Level 22 strike and man was that fun, but the gear dropping from it was level 18 for me.
Try get some vanguard gear, from memory the items cost 75-125 marks (weekly cap is 100)