Ways to get a number 1 defenseman:
1. Draft + Develop
2. Offersheet
3. A trade opening for an impending UFA (UFA must be leaving on his own accord for financial reasons)
Basically all three options are equally hard. Where #1 is concerned, you actually have to commit to drafting these players in high percentage areas of the draft. We've been conducting, posting, and discussing the math on this for years, but there was a huge period of time when the Flyers just didn't draft defensemen high. We could debate the reasons forever, but that left a visible hole within our organization. Fear of failure, comfort with success, market visibility before fluctuation...all solid theories, maybe not all incorrect or correct. Regardless of this though, we've moved on. 8 of the last 14 draft picks have been defensemen; some taken fairly high. This would've been unheard of for mid-2000's Philadelphia.
Where #2 is concerned, we already know this story. You can't always throw money at the problem even if you try your damn hardest to back the other team into a corner. Ed Snider played the game, and regardless of your feelings about letting Carle walk for free (I still can't believe that was a real gripe around here), going hard after Weber was the right idea. If you think we jumped the gun, then possibly. It's hard to tell why decisions are made the way they are, but fortune favors the bold. Waiting for Weber may not have been fruitful either.
As far as #3, see Pronger. These are the guys that don't make it to free-agency unless they're something sneaky going on; see Suter. Basically, you're still going to pay an arm and a leg, but in the end it's generally worth it. These situations are just as rare as #2 and as hard to contend with as #1 because it throws your ability to play #1 out the window. That's what happened to us anyway.
So realistically, teams just don't trade young, able-bodied and sound-minded #1 defensemen. It doesn't happen. There is no "we have too many of them" nonsense to speculate on either before someone from Toronto claims "take some of our awesome sauce off our hands." Particularly when it comes to defensemen, stick to the belief that if you're supposedly getting a deal, you probably aren't. Guys like Gardiner and Franson are not the deal you're looking for, and I can tell you exactly why. The deal you're looking for does not exist. You're just going to end up regretting it. vanRiemsdyk for LSchenn was different. We pretty much knew what the drawbacks and flaws of both guys were going in. We weren't looking at a lead winger for a lead defenseman. That was a complimentary winger for a complimentary defenseman. As far as looking for that one guy by trading key offensive players; any opportunity is a feint, a trap, a hoax.
So this leads me to my point. Keep calm, carry on, and for the love of god, don't trade Brayden Schenn or Sean Couturier, or really anybody. This team is built to develop like fine wine. We still need a number one defenseman, but develop him. Our team is young enough, and everyone knows we draft well. Keep our window never-ending and eventually you will strike gold. Also, always remember, depth wins championships; not elite stature.
LSchenn, Gustafsson, Gostisbehere, Morin, Hagg, Alt, Manning, Lauridsen, Larsson, Wilcox, and Valsiliev. Work from there. Your offense is already set long-term.