Are you using the 2-step method in your macros? They really helped me to increase my DPS. I've posted my macros for most non-melee classes in the sticky in the Macros forum. A number of people have said they've been helped by using them - I hope they are useful to you as well.
Haste and timing would have to be optimized through trial and error, but that would only increase your DPS by 2-4K or so at most. Your DPS is much lower than mine is, so optimizing based on haste is not your biggest worry at this point. DPS depends hugely on the fights, but in most fights that last more than 25 seconds my DPS is above 13K and many are at 17K or so. That's with the macros in the thread I mentioned before.
Good luck!
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