I know San’layn isn’t the preferred Hero Spec at the moment, but if you’re interested in gearing for it as Blood, you might want to consider changing your loot spec to Unholy. Blood loot spec is giving Crit gear, and from everything I’ve read so far, San’layn want to stack Haste to try and fit as many Vampiric Strikes in the Vampiric Blood window as possible. It also helps with Rune recharge timers.
I’m also curious to see how Rune of Unending Thirst might perform in a M+ environment