My other thought for a Letang Trade

Spurgeon > Letang
Zucker >>> Rust
12 OA >> 21 OA

Letang>>Spurgeon
Rust

Well I don't know how to type. Anyway, Spurgeon is not better than Letang. I don't see any evidence saying he is other than your carrots. Zucker is better than Rust, but really he's had one big year and comes in at 2M more than Rust. If you look at other years they're fairly similar but Zucker has more offensive upside. The picks might be a bit of a stretch to include.

Spurgeon better than Letang?
Letang finished 6th in Norris voting with 145 points and Spurgeon got one vote as some's #3 which gave him 5 points
Spurgeon just cracked 40 points for the first time in his career at 29 years old and Letang had 56

Spurgeon is not better than Letang, at all.
On the ice, Zucker is slightly better than Rust (even with Zucker's fluke 33g year), but considering contracts, no.
The only thing that you got right was the picks.

Letang >>> Spurgeon
Rust $3.5Mx3 >> Zucker $5.5Mx4
21OA <<< 12OA

That trade would be a considerable Wild win.