Depends on what you like. My brother more of a PVP player than I am did a lot of Crucible to buy gear and some pieces from vanguard. Me I cap out Vanguard makes each week and only do some PVP bounties, the "easy" ones. But only buy pieces to fill your spots you have lower gear in and upgade your highest light levels first. Can't go wrong leveling up Exotics (Helms first if you can) then level up you legendaries. Be sure to always have bounties, do the daily and hit the strikes (your level) or crucible. Then finish out with some patrols.