Alternatively, you can search on Youtube for videos from Sorc's PoV, preferably the same dungeons that you are currently running. There are plenty videos even with Dps meter visible. Then you can clearly see what you do wrong or what you can improve.
My guess, is that you have low dps back time. Dps from the front and side will greatly reduce your crit power and crit chance. And you probably idle too much because of whatever the reasons. Skilled players should rarely be idle even for one second during the fight.
exactly that a pro sorc just told me yesterday.
i actually always try to stand behind, but once i stand on the wrong side of darkan, i have to break my mana boost rotation, and then loost time on dps...something like that.
thats only one example but other things that stops my rotations still holding me back...i guess.