well about the trinket we/I use diff trinkets at diff. boss as u know some boss are pure dps race as the brutalis is and some are pure decursing or tactic/surviving ones so. I use on brutalis hex of shrunken head and serpentcoil braid (+hit/crit)/ Icon of silver crecent and the last mentioned trinkets are use because i dont have the skull from illi yet :). For serviving i use sorceres alchymist and battlemaster audacity. We mage suck on hp so therefor we sometimes "lagg" on dps for we need compensate hp for dps and therefore we need use such trinkets and gear.
About the brutalis fight our grp is with SP(shadowpriest) in every mana user grp and min 3 shaman but 4 or 5 would be better for upper dps and we have a moonkin which gives nice +crit buff too.
And the chain healing fromshamans is great and mages can IB when they got the "burn"