Giroux might have come back, but it was the right move not to resign him, problem was Fletcher was all over the place, trading G was right, resigning instead of trading Risto and then trading for TDA made no sense then.
Giroux went to Ottawa for his wife. He'll probably finish his career there, then sign for one day and retire as a Flyer.
He'd be worth bringing back if he could still play center, but as a LW will just block a prospect.
The Flyers have a few prospects with real upside in the system:
Bonk - he's the defensive backbone of London, which is trying to win the Memorial Cup again, he's not going to be flashy, but I'll bet he has a 10+ year career as a 22+ minute a night defenseman, similar to Niskanen
Jett - watching him on the Phantoms, he looked like an 18 year old (doesn't turn 19 until the end of August) but gradually improved, has first rate defensive instincts, plus passer, just defers too much to older players but will be a solid two way 2C who lives up to his name.
Barkey - the only question is his size and whether he can hold up in the NHL. Started slow this season due to mono, first 13g 1-11 12, next 37g 24-46 70, so far in the POs, 10g 9-11 20. He's the captain of a London team with Dickinson, Cowan, Bonk and O'Reilly, all 1st rd picks.
Zavragin - 19 year old starter on SKA, which is so choosy they exiled Michov to Sochi rather than play him. Has already started 58 games this season and won't turn 20 until August. His career trajectory so far matches up with goalies like Sorokin and Shesterkin. Has a chance to be special.
Other than that, the only prospect with top 6 upside is probably Grebenkin, big kid who has small player agility and puck handling. Guys like Bump are bottom six to me, Wisdom, Dowart, Powell, Gendron. Berglund is too far away to know, see if he starts in the SHL next season. Same with Ciernak. McDonald, Grans, Samson bottom pair D-men. Gill is also too far away to judge.