On offense they need and OT and A LOT of WR help. There biggest need is to stay healthy though.
In free agency they only need to target the offense. What that means is sign WR T.J Houshmandzadeh to a three or four year contract. Along with other WR’s that would help add talented depth. WR Mark Clayton, Laveranues Coles (would be #1 or 2) and D.J. Hackett. That would give Hasselbeck plenty of good solid receiving options. Branch would be either number 1 or 2 depending on what Coles would be. Then Clayton and Hackett would be three and four. Plus Hasselbeck already has John Carlson at TE.
The other need on offense that the Hawks have is offensive line. Mainly at LG and all around depth. They could look to sign one of the following, OT John St. Clair, Mike Goff or Tra Thomas. Anyone of those players would help the Seahawks offensive line and Hasselbeck out a whole lot.
Now for the Seahawks they are in a GREAT position because they need a great, strong young DT and Boston Collage DT fits the bill to a T. They have the 4th overall pick and it doesn’t look like the first three teams will take him. So that puts the Hawks in a great position to draft Raji. Then in the next rounds they could draft Safety William Moore from Missouri in the second round, LB Lawrence Sidbury from Richmond in the third round.
The way the Seahawks would fill the other DT need would be by trading either LB Leroy Hill or WR Deion Branch to the Kansas City Chiefs for DT Glen Dorsey. Having both Dorsey and Raji in the middle of the DL would give Seattle a great defense and if they all stayed healthy the defense could lead the Seahawks to the playoffs and with the offense on the same page it would make them a super bowl contender.