Assassins are building Titanic Hydra.

When was the last time anyone has used a Ravenous Hydra? Life steal is nice, but it's nearly useless on melee champions in this game. Either the enemy is a squishy carry, where having the Titanic Hydra's bonus health gives you more survivability than that 12% life steal ever could, or the enemy is tanky as shit, where your basic attacks are going to be worthless as you rely on your abilities to do all the work. And the damage Titanic Hydra gives is vastly superior to the Ravenous Hydra's. That's why Assassins take it: the extra damage and survivability is worth the slightly longer active cooldown.

The only people I can think of that would EVER choose the Ravenous Hydra over the Titanic would be champions that can use the Ravenous active mid-combo, like Wukong, who can't use Titanic mid-ult. And Pyke, because he gains no bonus health anyways.

Anything that does damage which scales off of tank stats is unhealthy to the game. Shen's taunt? Braum's slow? Volibear's chomp? Cho's chomp? Titanic Hydra? Those Spear and Atma's items that we saw on the PBE? Ornn's charge? They should scale off of things that aren't defensive stats. The only things defensive stats should increase are shields, self-regen, and damage resistances. Hell, you could make defensive stats increase cc duration, too. Nerf all cc and make it scale off of defensive stats. That would be fun.