^this, hydra is melee only while hurricane is ranged only
with that said hurricane seems to outclass SotD on every ranged champion and the latter will probably only be used in extremely niche roles such as to get very quick Q procs on Xin Zhao
hurricane+BT does seem like an extremely strong core (PD is more single-target DPS, especially with an IE though). aside from the lifesteal, hurricane works with twitch passive, corki passive, kog'maw W, MF W, and a lot more. also every hit will reduce graves's quickdraw's cooldown as well, so there's some pretty crazy kiting potential.
also just the idea of kiting three times as many people with ashe is hilarious
EDIT: I just realized that Blade of the Ruined King has a lot more synergy with Hurricane than The Bloodthirster does, especially with the pool of champions that can run the BT/Hurricane combo. You'd apply the proc on everyone you hit and you'd still have its active to kite more, plus you'd be healing a ton.
Another thing is that BotRK+Hurricane is much better on Kog'Maw than BT/Hurricane. Kog'Maw hates rushing Bloodthirster as it gives him a very weak mid-game, and while he'd be very strong if he rushed Hurricane, he wouldn't be able to stack up BT quickly enough if he bought it at around 25 minutes. BotRK lets you rush Hurricane, giving you a super strong mid-game (think about all the Kog'Maws now that rush Phantom Dancer) while getting BotRK for no loss and having some extra mobility from its active. Plus, he'd be EXTREMELY difficult to itemize against because he'd be doing huge physical and magical damage.