On my other character, I play as a tank. More specifically, I play as a PLD. My rotation is

Shield Lob
Flash
Circle of Scorn
3 combo set
Flash
3 combo set

I have trouble maintaining aggro, still, with this rotation. A lot of this comes from the DPS not attacking the same target I'm attacking, but when I play DPS and do this, most tanks are able to still keep aggro. Is there anything I can do to hold aggro better?