Stop timegating!
i think you are right about the catalyst being put out at the beginning of the tier. i think you are wrong about super high end single items like hunters bow. i.e., they should not exist. they pose the same problem as PI. if all the logs require a particular good luck to get item (or 2 PIs per pull) it just makes a whole lot of players who were not lucky enough to get the loot drop sad. side note, the lack of a bow drop should not have excluded Cruella from RWF. i remember never getting Withered J'im's trinket as a warlock. i am still bitter!
30% damage from thundering is pretty huge, maybe they should have made it so the tank is always in a group of three buffs though so that you never have to clear the tank.
correction LFR only FULLY opened TODAY. so no, not ALL difficulties were opened at the same time