If your Destro, don't DoT, just Curse and SB. Though I agree, you don't really have the stats for Destro yet. The biggst thing is your +Hit. You could pick up Asyen's Gift, Unfused Nethergon Band, Scryers Bloodgem, Voodoo Woven Belt, lots of good PvE choices out there. The PvP gear your wearing is horrible for PvE. get a better Metagem, and get rid of the intellect and Stamina Gems. Quit going for socket bonuses and get pure +hit, pure +spell dam or the +hit/Spell dam gems like you have in your chest, until your hit capped.
Check out this gear guide:
http://wowmb.net/forums/showthread.php?t=23586
Sorry, don't usually like linking to other sites, however, we have nothing like this here.
In the sources on that guide is a link to the Warlock DPS Spreadsheet. Get that, plug in your gear, then plug in different Specs to see how you can maximize your DPS. You can also plug in different gear your thinking about getting and see how much of an increase it will be. Also, don't expect to reach the DPS it says, as that's in a perfect world with no movement and little lag, which is rarely thee case.