As i heard our stat prio is agil>crit(25% unbuffed so buffed pushes u to 30%)>mastery=multistrike>haste etc..If you can get 25% crit from gems/gear u can enchant mastery i guess.Since we find more gear with mastery in HM,this stat becomes best after crit cap.
In BRF we find plenty of gear with multi so our stats will be agil>crit=multistrike>mastery.Then we will enchant multi on weapons.