A stronger MS is needed anyways no matter how you try to turn it. At the end of wotlk you had a 50% heal debuff which was absolutely needed in alot of fights where healers were involved because resilience stacking was so effective for healers.
Even now, at the START of this expac you got some healers running around in 3000/3500+ resilience which amounts to around 30-36% damage reduction already. And values will grow with each season. Yet you only got 10% heal debuff which makes them even stronger than at the end of the last expansion. Sure, they dont have as much burst heal anymore, but dds also dont have as much burst damage anymore so that evens out.
Things will get tougher for non healers soon with more resilience and even lesser chances to kill a healing class. Wait a few seasons and I am sure that blizzard will have to react to it and either nerf the value of resilience or buff MS effects again, or we are back at world of healercraft snorefest.