i am a casual player as well but first i would recommend azortharions guide on icy veins:
NOT ALLOWED TO QUOTE URL! lol
there you will find anything you need. For Raiding as MM there aren't many choices you can make, it's all pretty straight forward i think.
A few things i can see in your armory are:
- Steady shot. Don't do that. Bad bad tauren! Alwayse lone wolf
- you are missing enchants on your rings
- bracers are not very good for MM but i suppose you don't have any other?
- i would switch the legs for something else till you got the 4 pc bonus. I think even 910 legs with mastery will perform better until then
i cannot find any logs from you so i can only guess that there are issues with your rotation. Rotation is everything.
hope i haven't told any crap
edit: NVM, didn't see your edit, read it now :P