That deal is horrible for Ottawa

Not really. JVR still projects to be a 25-30 goal scorer and Ottawa has little to no cap commitment during the remainder of his contract, plus they clear their own bad contract away

Edit: Looking at Ottawa's current situation, JVR would be the 2nd best winger on the roster by a large margin behind Brady barring Stutzle coming in and exploding year one.

Ottawa is trying to go young, and rebuild through their insanely good prospect pool, can't see them wanting JVR.

Also, Melnyk is cheap, with $19M in salary due, and them already reaching the floor once they sign the rest of their roster, I can't see this as a likely scenario

I doubt if Ratcliffe lands Gallagher. I think Bergevin would ask for Farabee in a trade for Gallagher, which I don't think Fletcher would be fine to give away. Maybe switching Ratcliffe for Frost might do it for Bergevin as well, cause he's definitely looking for someone who can play now.

If Gallagher is traded it will be at the deadline, when is value is at his highest and after months on negotiating.

He can still play, but he's firmly into the decline of his career, and his value is pretty significantly negative given the massive contract. The market to dump players like that is razor thin, and it's not going to come cheap to dump that kind of money especially with three years left. Sens don't need to be in the business of doing favours for free.