So what your saying is that Raji won't be a starter for several more years. Kennedy is actually older than Williams. MN does have a young guy who they are working with. Guion. Since as you said, it may take several years for DT's to develop, we won't know for awhile.
They also had a non-first round player finish up the season the year before and play in the playoffs. And being a first rounder is no guarantee of sucess. Look at one of the Packers two first round QB picks in the last 30 years. How long did Rich Campbell, (6th pick overall) last in the NFL? Just for reminders, his career stats.
31/68 386 yards, 3 TDs, 9 INt's, 7 sacks and a rating of 38.8
List of NFL starting qbs (2009)
New Orleans: Brees: early 2nd rounder (32 overall)
Carolina: Matt Moore: undrafted
Atlanta: Matt Ryan: 1st rounder
Tampa Bay: Freeman: 1st rounder
GB: Rodgers: 1st rounder
MN: Favre: early 2nd (33 overall)
CHI: Cutler: 1st rounder
DET: Stafford: 1st rounder
PHI: McNabb: 1st rounder
WAS: Campbell: 2nd rounder
NYG: Eli: 1st rounder
DAL: Romo: undrafted
SEA: Hasselbeck: 6th rounder
AZ: Warner: undrafted
STL: Bulger: 6th rouder
SF: Smith: 1st rounder
IND: Payton: 1st rounder
JAX: Garrard: 4th rounder
HOU: Schaub: 3rd rounder
TEN: Young: 1st rounder
PIT: Big Ben: 1st rounder
BAL: Flacco: 1st rounder
CIN: Palmer: 1st rounder
CLE: Quinn: 1st rounder
NE: Brady: 6th rounder
NYG: Sanchez: 1st rounder
MIA: Henne: 2nd rounder
BUF: Edwards: 2nd rounder
SD: Rivers: 1st rounder
OAK: Russell: 1st rounder
KC: Cassell: 7th rounder
DEN: Orton: 4th rounder
As you see, 56% of the NLF starting QBs last year were 1st rounder, and if you take into account that Favre and Brees were very early 2nd rounder, it goes to 59%.
If you take into consideration last years' top 10 qb by rating, 40% of them are 1st rounders, 60% if you count in Brees and Favre:
Brees: early 2nd rounder
Favre: early 2nd rounder
Rivers: 1st rounder
Rodgers: 1st rounder
Big Ben: 1st rounder
Payton Manning: 1st rounder
Shaub: 3rd rounder
Romo: undrafted
Brady: 6th rounder
Warner: undrafted
46% in the top 15 (or 60%)
Eli: 1st rounder
McNabb: 1st rounder
Flacco: 1st rounder
Orton: 4th rounder
Campbell: 2nd rounder
55% in the top 20 (or 65%)
Palmer: 1st rounder
Garrard: 4th rounder
Young: 1st rounder
Smith: 1st rounder
Ryan: 1st rounder
Now, considering the young QBs (under 30) in the list, it goes to 66%:
Rivers: 1st rounder
Rodgers: 1st rounder
Big Ben: 1st rounder
Shaub: 3rd rounder
Romo: undrafted
Eli: 1st rounder
Flacco: 1st rounder
Orton: 4th rounder
Campbell: 2nd rounder
Young: 1st rounder
Smith: 1st rounder
Ryan: 1st rounder
So, yeah, you can find a starting, quality QB outside of the 1st round/early 2nd (top 5 2nd). But odds are against it, specially nowadays...