More defensive options for ADCs

Regardless of whether we're in the Cinderhulk meta (where tanks, coupled with their cc and damage can almost single-handedly kill a carry) or the Devourer meta (where despite condemning and rolling away from Udyr, can still catch up to you and kill you in a stun and a few autos,) there's not a lot of item choices concerning builds against hybrid damage team comps. All AD team? Randuins. Heavy AP? Banshee's. Mixed damage? Guardian... angel? I don't see much use for this item for a carry for very simple reasons:

• the carry is dead, so chances are highly likely the rest of your team will either be killed off or be unable to defend you as you finish reviving, in which you'll just blow up and die again while 3+ members of enemy team surround you.
• it doesn't offer enough armor/magic resist to prevent you from blowing up (no health stats, as resistances are only good as a combination)

While the game meta doesn't necessarily cater that well to assassins like Zed, Talon, or Leblanc that well anymore, fighters and tanks are providing enough cc and damage to reach and kill carries pretty easily, especially in solo queue. And I know positioning is probably the single-most important thing to master as an ADC, but in a team comp against say Udyr, Jax, and Diana, it's literally the worst experience considering your attack range puts you right within range of getting jumped on, beaten up, and eaten alive. It's becoming much less relevant of a role when their fighter can just walk up or jump onto you and kill you in an instant unless your team actually offers some decent peel. And I'm sure a lot of you can contest that solo queue is probably the place where that's least likely to happen. Not to mention the game is a complete mess of cc, from item actives to ridiculous champion abilities (hello 3-second morgana root, fiddle silence, malzahar silence, malphite ult, etc.)

TL;DR My Proposal:

Why not add a new item? An item offering: health, armor + magic resist, along with a ranged-only passive that offers tenacity? I'd love to see something like this open onto the PBE sometime. Thoughts?

P.S., not a fan of Mercurial either. It's bad enough being forced to buy a 1250 gold item for peanut magic resistance and an active good for (1) one crowd control effect, at which point you're most likely already dead anyway.