I moved this post into its own thread to comment on it - it seemed different enough from standard UR Delver to warrant discussion (apologies to Cunningbeaver if this was unwanted)I played this list, with very minor modifications, to a 3-1 in a vintage daily last weekend. The only changes I made to Cunningbeaver's list were +1 Sudden Shock maindeck and +2 Sulfur Elemental in the sideboard, a concession to the fact that Cunningbeaver made that list before Mentor was a thing.
I liked Deathrite Shaman all over, it felt like a natural fit in the deck, though it does make the already shaky manabase even shakier. I don't think that cost me any games, but it easily could have.
Burning Wish was solid, but not mind blowing. It didn't give me any help in the scary Oath/Dredge matchups, and sometimes Wish->Cruise or Wish->Walk were too slow when a natural Cruise/Walk wouldn't have been ... but that's not an entirely fair comparison. In the games where I hoped the Burning Wish was a Time Walk, there would have been a 2/3rds chance it wasn't, if I wasn't running Wishes at all. Most of the time the Wishes weren't too mana intensive, anyway.
I'm sure Grapeshot is not correct, though it was relevant in my games ... it was just too fun not to run. In a deck with so little mana development, you don't have the same options with Wish that other decks do ... but Time Walk and Cruise are good enough for most circumstances.
Edit:
Here are some highlights from the daily if anyone wants to see the deck in action!:
Burning Delver vs 4c MentorBurning Delver vs Forgemaster Stax