In my opinion (I play SCH /BLM/ WAR in frontline) the interruption are something really annyoing, but affectively needed, expecially for healers, because the healing power is much higher then DPS power, and the healer role during FFXIV PvP, as someone said before, is "survive as long as u can".
For DPS "maybe" something could be adjusted, but I'm not aiming for an interruprion removal at all.
As BLM I can be interrupted even by autoattack, pets-attack (there is always a stupid garuda on me -.-), stunlock and silencing even during Equanimity/surecast, BUT u can be interrupted even if the target run away from your range or simple go to your back.
Up to me THIS is really a pain, I agree that a melee have to reach u to attack u, but once that he reach u.... hem... it's really hard, u can bind him 1 or 2 times, hoping that your friends don't attack him soon, but up to now if a bard focus u, u are fucked up.

My suggestion would be to ignore interruption caused by autoattack or pet attack. But I really don't know how it could impact on a match, I'm not a developer :/
Or something more "hard to do" that after any attack to you you gain a stack that in 4-5 second will wear off, but if u will be hit again in that range of time you will gain another stack, once u reach 10 stack you gain 5 sec of equanimity, so damned chaser won't just have to follow u in a brainless way.
Or maybe any attack directed to you lower the recast time of Equanimity by a little.