You will never reach your maxed sim, because you have downtime when you move out for fading light, and hour of twilight even if you do it 0.1 sec before. One dot tick while you are passive/do not do any direct damage destroys dps.
This is for example the reason why sometimes arcane mages have a much higher dps than people doing more total damage. They are the only class missing any form of dot.
Edit: As for your personal dps, I'm not very experienced with elemental shamans, I just wanted to point that out, so that you don't bash yourself too much.