Revivification is obviously not designed to keep anyone alive while under pressure. The change to it (faster cast) isn't beneficial in the sense that those massive powerful circles on the ground are now keeping a pressured healer alive. It's that because they're fast casting you no longer have to worry about the worst case scenario where a DPS have you completely beaten by interrupting you at 0.1s left to cast and then stun you. This is the same reason why casting Dark Infusion/Deliverance is dangerous, because you risk taking 6 seconds of concentrated DPS. Actually it's even worse in the case of Revivication, as the amount it heals is certainly nowhere enough to keep any DPS off, so often a perfectly valid strategy is just let the Sorc finish casting his Revivification and just DPS him through it. Prior to 2.0, it took a lot of guts to cast Revivification because it's basically a free invitation for 6 seconds of focus fire. In PvP, the difference between 4 seconds (straight up stun) and 6 seconds (interrupted at the last 0.1s of your heal) is an eternity and with the change to Revivification you're usually looking at ~5s in the worst case, which is something you can live with.
You are basically arguing against yourself now. If innervate is on cool down, the only big heal I have is dark infusion, which you just said is a risky cast. Otherwise its dark heal (also channeled) which is not force efficient and crits for 40-50% less.
The only 3 spells I can use while moving and heal are 1) cleanse, 2) shield and 3) resurgence. Otherwise I have to stand there (even if reviv is 2 stacks, I still have to stand still)
Im just not sure how sorcs are overpowered...