What I am referring to is more like domination where the buff is on you and works on any mob, not just the one that you triggered it on. It would also last far longer.
They could even make it affect teammates. Then they could play around with different buffs to give sentinels some utility. Like press one button and do an AoE regen/recovery buff or press the other button and give out a resist/def buff.
It would be where domination is self, but opportunity is for everyone in an AoE.