Or you just remain patient, make changes around the edges and wait for the kids to grow up - which doesn't take forever.
You look at the kids making big contributions in the playoffs, a few are 20-21 like point, but most are 22-24 years old with 3-5 NHL seasons under their belt - the point where they have physically matured, and have enough experienced that nothing fazes them. Then your youngest prospects are at the bottom of the roster and can be sheltered until they show themselves ready.
Now look at the Flyers potential 2019-2020 roster:
Couts (27), Patrick (21), Konecny (22), Lindblom (23), Frost (20), Ratcliffe (20)
MV (26), Bardreau (26), Laughton (25), Vorobyev (23), NAK (23), Rubtsov (22)
Ghost (26), Provorov (23), Sanheim (23), Myers (23), Morin (24), Hagg (24), Friedman (24)
Giroux (32), Voracek (30), Simmonds (32) if extended, Gudas (29)
So it's not like you need to add a half dozen guys through trades and free agency the next two years to fill out the roster.