you better win this year, because your cap is F 'ed next year.

It'll be tight like most teams, but they'll be fine. ~8 million coming off the books with Laughton, Raffl, Gus, and Elliott leaving plus whoever Seattle takes. That'll be enough to resign Hart, Sanheim, and Patrick while filling the other holes with ELCs.

it's the depth that leaves that kills teams.

Only Hart, Sanheim and Patrick to re-sign with almost 13 mil coming off books, without expansion or trade of JVR or Ghost, Philly is fine cap wise

Their forward corps is so deep

I'd be willing to guess one of JVR, Voracek, or Ghost will be taken by Seattle. They're not in as much cap trouble as you think. Voracek and JVR are still good players and put up 20 goals almost every year. With retention they can be moved fairly easily. Ghost is one I'd be more concerned about moving.

it depends what guys get paid and who seattle takes. Don't count on Seattle to take up cap. Not when they have a whole ton of guys that are considered dumps worth 1st round picks with 2 years left on contract. They could easily help those teams and claim a 1st from like 5-7 teams if they wanted to.
It also depends on what guys get paid. Hart wins a cup....watch out. You'll have one of the most expensive goalies in the league. You'll have basically no leverage to say otherwise. If you are looking at 13 million prior to seattle picking, you will be screwed. He could ask 10. Even if he doesn't win a cup. On a long term deal it's probably 8 mil. Sanhiem 4-5. You are at 13 with holes to fill.
It's part of the pain in the ass of having good players. Philly is lucky in Hart is one of the best goalies in the league. Not best young goalies...best goalies in the leauge. He'll get paid like it. As paying younger guys is now the trend. Thank TOR for that.