the only buff i woul like to see quelling strikes needs a 50% instant agro drop (like DRG jump) as soon as u use it.
the only solution to your problem is giving the fresh tanks more time ....wait for 2-3 overpower / flash before start dpsing , or slow down a bit...at the beginning.
I didnt had any problems as fresh warrior/paladin , OP and flash spam was enough to keep up. For bosses FoF/ berserk at the start and u are golden.