We know with a fairly high level of confidence that the Blues looked long and hard at a deal of Nash at, I believe, $1.8MM retained for Shattenkirk early last year. That was meaningful value – so at least one team was considering a deal that wasn't pennies on the dollar.
If the Rangers are willing to retain the full $3.9MM on a top 6, plays in all situations winger, who can occasionally dominate a game, who has now proven himself to be healthy, that again is definitely is worth real value.
As to why he might be easier to move than last year, remember, back then he was a) coming off of injury, b) the cap barely had barely moved and c) most importantly, the looming expansion threw everything off. Once the wild card of the expansion draft is over, with only a year left on his deal, and with retention, he becomes MUCH easier to fit on another roster.