This is only pertaining to you if you are planning to play deep into the future.
Well first off you are going to need to get bigger on defense. You'll have a lot of base talent with the Eagles to with with: Babin, Cole, Samuels, Namdi, DRC, Cullen Jenkins. Jenkins could easily shift from DT to DE for the 3-4 but Babin and Cole have got to go. I think you could trade them separately (along w another player) to anyone for a couple solid 3-4 Ends or OLBs. Up the middle id stay put with Casey Matthews, he gives you a solid guy to hold down what is going to likely be a work in progress LB group.
DT:
This is the key to the 3-4, you got to go out and get a Raji, Knighton or a Wilfork.
DBs:
since the rest of the team will be in rebuilding mode id keep Namdi to hold it all down, and id also keep DRC so that you have a speed corner who will make plays (they will have to challenge him a lot). I wouldnt worry about Safeties, they are easy to address in the draft.
QBs:
I would definitely ship out vick in exchange for a young QB, maybe even for of the 2010 draft guys, just make sure you get some draft picks or guys to fit your system.
TE:
Celek will need to be shopped out of town, maybe look at the Gronkowskis from NE.
WR:
Id keep either Maclin or Jackson, but not both. Id also ship out Steve Smith. your going to need to find Benn from Tampa, James Baldwin, or Julio Jones, solid young guys who have the ability to be physical. Id also trade Schmidt (FB) for a run blocker like Vonta Leach. Since Jackson is your biggest trade draw i would definitely use him to pull in a top shelf LB like Von Miller or Aldon Smith....
If you trade your strong points to teams who need that position, in exhange for positions that other teams have surpluses at, I think you should be able to find a way to create something like this:
FS:Page
SS:Coleman
CB:Namdi
CB
RC
SLB:Akeem Ayers(Ten)
MLB:Matthews
MLB:Colin McCarthy(Ten) Babin+pix/ plyrs could get Ayers+mcCarthy)
WLB:Von Miller(Broncos) (Jackson deal)
DE:Jenkins
DT:Knighton (Trent Cole Deal)
DE: Dareus (vick trade?)
WR:Benn
WR:Jones (Maclin Deal)
TE:Gronkowski (Celek / Steve Smith pix/players)
TE:Gronkowski
FB:Leach
RB:McCoy
QB: Deal vick for any game manager + draft picks. If you could find a way to deal Vick and a draft pick or another player for Fitzpatrick + Dareus u would be stacked.
Everything else you can attack in the draft, just make sure u go for depth on the DL and OL and keep your team strong and physical. Find a QB who just manages games, WRs who run routes, and RBs who dont fumble and break tackles, dont focus so much on speed...but rather acceleration +strength.
If you got this roster made, you probably are running low on depth and draft picks, but, you are going to have some legit pro bowlers across your defense and you are going to have a lot of young talent to use as trade bait to help bolster your team throughout the years.