Urabrask won't count copies of instant and sorcery spells that were created on the stack and not cast
Serra Avatar You already have more than the usual 20 life in EDH, and you usually pay seven mana for a 20/20 (or at least a 15/15) in a slow format
While losing Settle the Wreckage does hurt against creature decks, the addition of Shield Mare and Baffling End does give us some more good sideboard options to help against aggressive decks, so hopefully the damage will be mitigated
"The idea of it is a deal with the devil, right
Some of these spells have the Convoke keyword, which enables us to tap our commander to cast the spell
While the original is generally used as a way to protect a combo going off, Serenade doesnt hit instants or sorceries, so itll have a different use case, probably more as a tempo card