Dies to Removal

Yeah, my group never seems to care which makes it a wonderful inclusion. The Sphinx is an insta-kill though

Hell, I'd play both Study and Sphinx. If you're diligent with Study, you'll draw a ton of cards because no one ever wants to pay 1 to stop you. Sphinx is just a beast in EDH and should be played in every blue deck.

May want to look for undying creatures as well. Getting to sac creatures more than once is always a plus.

I forgot about the Foundry having blue in it. Have you considered running Athreos, God of Passage? It's so at home in a Vish Kal deck.

I think the easiest way to go with Vish Kal is to focus on token generators and sacing them to pump Vish and win via Commander damage. You will also have your back up win cons, but in BW, token generators aren't hard to come by and you can always use things like Trading Post and Thopter Foundry to pump out a bunch of critters