As it stands they don't really have a future right now. Barring absolutely insane development curves McMichael, Lapierre, Alexeyev and Protas become supporting players. Good to have if cost controlled but other teams sign college talent/Carter Verhaeghe type cast offs to same or greater effect. Might get an Oshie level there if you're lucky with Protas showing the most right now but probably a bunch of Milano/Eller/Sheary level guys. All the work in acquiring new franchise players will have to be done, hopefully by a GM who doesn't give away a team's worth of talent (Stephenson, Burakovsky, Samsonov, Siegenthaler, Vanecek, multiple 1st/2nd rd picks) for nothing just so he can accomodate the quirks of inept coaches he hires and is great at finding talent instead.
I don't see a problem with turning around and using the picks we get for UFAs to get some temporary high end players to make the next 3 years awesome. Ovechkin remaining hot is not a given as we are seeing now, nor is him not falling off a cliff at 38, 39 or 40. I wouldn't bet against him but plenty of very good players have cratered at this age for many, many, many different factors.
Backstrom should stay honestly, be it as an expensive 3C or LTIR. Not ideal but every team has one of these contracts and still finds a way. Bruins went to the cup finals in 2019 with a 6 million dollar Backes facing a Blues team with a 5.5 million dollar Steen both of whom combined weren't even what Backstrom is now.