Why are you pointing out his last deal? That has nothing to do with what he may or may not get this time around. He is much improved in the last 4 years, and you are kidding yourself if you think he is getting less than 5 mil/season from anyone. David Clarkson had one 30 goal season and got a 7 year deal at over 5 mil a season. Nielsen is a fairly consistent 2nd line type player who can PK and plays a two way game.
In my opinion he will easily get 5x5 from someone. Have you seen the inflation of weak UFA's anymore? Weak players pull in awesome deals all the time. Jeff Petry for pete's sake got a 5 year deal, he a 5th-6th talent dman at best.
I pointed out his last deal because you brought up Filppula, and Nielsen when he signed his last deal was more comparable to Filppula than he is now, yet he only received $11M over 4 years. And now he's 4 years OLDER. So Filppula doesn't really work as a good comparison. Nor does Petry; he's also 4 years younger and also plays a different position. And Clarkson is a terrible example.... yeah, there's been wacky contracts handed out over the years, but those are the exception to the rule, and there's no reason to believe that Nielsen is going to get a contract in line with the craziest ones of years past.
Nielsen is not much improved over the past 4 years. He's virtually the same player (which is a testament to his consistency).... great two-way guy, aptly plays the PP, is near-lethal on the penalty kill, has a high compete level, is not very physical, and is below-average in the faceoff circle. That's what he was 4 years ago, and that's what he is today. Oh, and aside from a small spike two seasons ago, his point totals have been pretty much the same for 5 years straight.
I can see Nielsen getting $5M per year, but most certainly not for 4-6 years. That's what I disagree with. If he were 28, like the players you compared him to, and like he was when he signed his last contract, I might agree.