I kind of think both Nash and Yandle will not be the same players in like 2 or 3 years, not sure I'd want to see the Rangers keep either.
Although I know it's a pipe dream I'd really like to see them reboot to a point regardless that Lundqvist is getting older.
I think they could use the return from Yandle now, Nash this off-season, and then even Klein when he is a UFA to be to come close to rebuilding their farm while making the on ice roster younger too. Let some other team find out at which point those guys decline, because I think Nash is already showing signs and Yandle will too in about 2 or 3 years. Injuries just pile up and they just don't heal the same as players get older.
Use the extra cap space to re-sign the youth, maybe skip some bridges if the cap hits make sense on some of the more reliable players, sign short term one year vets that can either be sold at the deadlines or re-signed cheap if they work out.
Stop buying at the deadlines, finish where they naturally do, if you can not get back youth/picks at deadlines and they still really feel the need to go for it stand pat or only add in cheap stuff for like 3rd round picks.
Set limits on the UFA targets, Glass should have had a limit of 500K, Boyle 2.5M who cares if they go somewhere else, that is what they are worth to this team. There are cheaper options who can add just as much if not more.
Sell picks at the draft need be when they are worth their most. Buy picks at deadlines when they are available for less.
Be a little more efficient in every way and instead of coming close and having windows the team will always be pretty good, and some years very good.