Quick thought: We've heard a lot about drafting/building the OL before getting the QB, but that's not the only way to do things. Since I maintain that drafting the best players is the right approach to building the best team, as opposed to drafting for need, I went back through history and looked at a few of the top "dumpster to dynasty" turnarounds and saw how they drafted.
The Cowboys of the Jimmy Johnson era (88-93) showed the blueprint for a rebuild. But they took Michael Irvin (11 overall) first in 88, then Troy Aikman first in 89 (1 overall) and then Emmitt Smith first in 1990 (17 overall).
How did they build the dominant OL that helped them win 3 Super Bowls in 4 years?
LT - They signed Mark Tuinei as a UDFA in 1983 as a DT and moved him to OT in 1985
LG - They signed Nate Newton as a free agent in 1986 when the USFL folded.
C - They drafted Mark Stepnoski in the 3rd round in 1989 (same draft year as Aikman)
RG - They traded a 5th round pick for John Gesek in 1990
RT - They drafted Erik Williams in the 3rd round in 1991
All of them except Gesek made at least one Pro Bowl. 2 free agents, 2 draft picks (none first rounders) and one modest trade.
Point is simple... there is no one single formula to build a great team, or to build an OL. And the Cowboys acquired 3 of their starters after they drafted Aikman.
(Not included, they drafted Steve Wisniewski in the 2nd round (29 overall) in 1989, after taking Aikman. But they immediately traded Wisniewski to the Raiders for picks that would land them Daryl Johnston and some scrubs, and Wisniewski went on to have a borderline HoF career for the Raiders, making 8 pro bowls and the 1990 all decade team)