That's not bad from a Jackets perspective.
I was thinking along the lines of:
Dubinsky
Milano
2019 First
For
Nelson
Yours is close to that, minus the cap offset from Clutterbuck and the inclusion of Harrington and MDC + 2nd.
Why the Jackets do that:
It moves Dubinsky's cap and replaces him with Nelson who is an RFA and a bit younger. The big risk is if they lose Panarin and/or Bob and end up missing the playoffs, that 2019 1st would be quite valuable. However, I think Dubois, Wennberg, Nelson, Nash down the middle is pretty solid.
Why Islanders do that:
They get Milano and a 2019 1st (unprotected). I think given adequate opportunity Milano could play a good top-6 role similar to Grabner. I think his game would match Barzal's well. Also, Dubinsky is serviceable in the 3rd or 4th line center role albeit overpaid and north of 30. The Islanders would have to essentially eat his cap for the next 3 years so that's the biggest downside. If they have big plans for their cap in the near future then it'd be a no-go.
Dubinsky has an NMC but he may waive to play under Trotz and used to live in NYC.
Nelson is an RFA but honestly I think re-signing him would be easy for either team.