There wasn't much purchase on this wicket for spinners. This was a "mix it up and make the batsmen work hard for runs" type of a wicket. I dont think Solanki or Theekshana would've helped on us. This wicket needed a Pretorius.
I hope Simarjeet is having some issue and that's why he was benched. He looked good last season with Mukesh, and he should replace Tushar ASAP. I would even have a look at Matheesha Pathirana, who got Dhoni praising him to the skies towards end of last season. Maybe he could be our death option like Malinga.
I think you'll always find a use for an attacking spinner and while Theekshana isn't as aggressive as your wicket taking spinners in the mold of Rashid, Hasaranga etc... he's still more useful than Santner if the latter isn't bringing his WC form. I agree that Pretorius is a necessity with the lack of death bowling options anyway. Sunk cost fallacy would mean that Stokes isn't getting dropped even if he should be the one who should be. Conway might be harshly axed as Dhoni at eight with batting depth below is a little too much. As shown by today most teams won't make use of that much batting depth even if it is available as they're firmly rooted in old ways unless it's England.