Exceptions - top teams do it well at the TOP
Recent ESPN report on the draft noted that 18 of Pittsburgh's 22 starters were obtained through the draft or undrafted college FA!!!!!! Also, even if you just look at their #1 picks:
2005: Heath Miller - starter and probably future Pro Bowler
2004: Roethlisberger - Pro Bowler
2003: Polamalu - Pro Bowler
2002: Kendall Simmons - starter at guard
2001: Casey Hampton - Pro Bowler
So of their last five drafts the Steelers have 3 Pro bowlers and two starters. That is how you get to the Superbowl. Contrast this with our FO developmental picks (Kennedy in his 4th year will 'come around', Lewis is coming, even Pickett had never sniffed pro bowl status, Jackson is solid but no star (yet), the best hope is Barron).
For the investment your top choices should be Pro Bowlers (at least the majority) and not 'solid starters'... I say trade up get the impact players and forget this trying to get depth from more middle round picks.