I'm trying to find the thread but there was one on NHL Talk within the last month or two. IIRC, LatvianTwist did the math and it wasn't as significant as we think.
I think the Kucherov contract is also a bit of a discount because he wants to play there. If he was on Florida, I'd venture a guess he would NOT be taking 9.5 to play there.
I mean, if I was a player I'd take less to play in Tampa. Taxes aside, the city is nice, they have a beautiful arena and a great team. When I saw the Rangers play in 2014 at Amalie arena I was so impressed with what the Lightning have.