first of all crit is better than haste even before 3056 cap. Dont sacrifice Crit for haste ever.
At some point around BiS gear this tier Mastery > haste.
i assume you are no where near BiS, as you would not ask this if you were =)..
so your prio is Crit>>Haste>>>>>mastery. That is the simple answer i can give you.
The not so simple answer is start running Simcrafts of your char every time/few upgrades to keep track of how your stat values are. If your not comfortable with using it ask your guild if any one is using simC if yes ask them to run the simC's for you..