Turtle WoW

There is only one bis shield in game.
But we talk about legendary shield, not about meditation or some items.

Shield is not bis.
Ring was nerfed and now it doesn't have mana reg.

Shamans don't have meditation in bis raid gear.

Eye of Sulfuras is not for healers.
Atiesh for druids doesn't look mega legendary, but it has spirit and buffs party with mp.
Shaman's bonus should also give addiotional mp5, but more, because we don't get mana reg from spirit.

Druids and priests have Atiesh, but shamans and paladins have nothing. Since they both can wield shields, it would be logical to add a legendary shield. Shaman's legendary bonus will be like "your water totems now XX% stronger" or "your water shield affects all your party members".

Developers can make talents that already existed in old versions of WoW. We had Earth Shield in TBC and Riptide in WotLK. But Earth Shield is good only for one shaman in raid, and Riptide will not stack as other hots. Maybe last talent should be improved version of Chain Heal. Your Chain Heal heals ...

How do you think, what new last talent would be good for resto shaman?

There should be reason to play in deep resto spec.
Now players can be normal healers in ele/resto and enh/resto specs.

No...
It's not just heroic version of MC, it's different.
You do this MC as a challenge, and new loot will not help you in another raids, it will be good only in this raid.

It's very hard for turtle team to create new raids, they spent many months for Emerald Sanctum with one boss.

The Idea of heroic MC is unusual challenge, not just another raid with loot.

Hard version of Molten Core for 40 people, where your Naxx gear means nothing, only skill matters. You must have fire resist gear in EVERY slot not to get oneshot on boss/trash fight. Vendor will sell starter gear (even weapons), but to get better pre raid resist gear you should do quests, run dunge...