Um. Why does Arizona want Shattenkirk? They have a decent defense already.
Ottawa is not taking on real money for a guy that cost virtually nothing due to insurance.
Doubt Toronto makes that deal.

Zero chance Toronto takes 3rd liners and a pick for Nylander.
I don't see the value in that Arizona trade either.

Vesey for a 3rd and gaborik and they'll buy out smith -- cost is minimal. They are stockpiling young players and picks, this gives them that for limited cost.
Arizona only has demers as a right handed shot. Both Shattenkirk and Stepan under-performed last year.
Toronto needs to save money. Buchnevich will cost significantly less than Nylander, the age difference is not that much. Buchnevich hasn't had the same supporting cast, and he still puts up decent point per game numbers. Howden can replace kadri if they trade him and a 2nd is a decent pick

Yeah I wouldn't take that deal for Nylander. The Nylander deal would be pretty easy. It's basically just Skjei straight up.

Not sure what you mean. Smith and Vesey make a combined 6.6 million, where as Gaborik is on IR and his 4.88 million dollar contract is covered on insurance and cost Sens pennies on the dollar. There is no savings for Ottawa only Rangers.