That one is easy:
TT has to sign Randall Cobb. He's an ascending flexible multi-talented strong offensive weapon.
He's arguably headed to being the teams legitimate NO. 1 WR. After him and Jordy Nelson and inspite of the promise Devante Adams showed in a rookie season; we have little guarantee at the position regarding depth.
The strength of the team is obviously on Offense. Randall Cobb played at a Pro Bowl level.
As good of a season as RT Bryan Bulaga had in 2014; his past injury history (hip and knee) and missing > 50 % or 27 of 53 of his games 2012-14 is a risk exceeding Randal Cobb's and the question of availability.
With an either / or question:
Sign WR Randall Cobb.