I understand where you are coming from, but I have to admit that I disagree with virtually everything you say here.
1) The "you can find a late round RB" is largely a myth based on a select few RBs that people can point to (Benny/Foster/etc). The problem is that the vast majority of those late rounders wash out while you are much more likely to get guaranteed contributions from a higher pick. On top of that, NE's actions speak loudly that they didn't just want fillers on the backend of the RB roster, they agressively targetted the position to improve the top end.
I disagree that it is a "myth." If you look around the league, the RB position has plenty of guys from the 3rd round or later that are quite successful. Ray Rice, Jamal Charles, and Shonn Greene were all 3rd round picks. Arian Foster and BJGE were undrafted free agents. Ahmad Bradshaw was drafted in the 7th round. Michael Turner was drafted in the 5th round. Blount, Woodhead, Fred Jackson were all undrafted. Frank Gore was a 3rd rounder. Marion Barber was a 4th rounder. Ryan Grant was undrafted. James Starks was drafted in the 6th round. Pierre Thomas was undrafted. Brandon Jacobs was drafted in the 4th round.
Of course you're going to have some top flight guys like Chris Johnson, Adrian Peterson, Mendenhall who were all drafted in the first round and are top performers at their position. But what other position in the league has so many mid/late round or undrafted guys that are successful? None. Every year there are running backs that seemingly come out of nowhere and produce.
2010 in Cleveland. Their 2nd round pick, Montario Hardesty, tears his knee up in training camp. Peyton Hillis, a guy that only touched the ball about 15 times in 2009 with Denver and many people only thought of as a fullback/H-back posts 1100 yards and 11 TD's.
2010 in San Diego. Their first round pick, Ryan Mathews battles through an injury plagued season. Mike Tolbert, an undrafted guy from Coastal Carolina, comes in and puts up 700+ yards and 11 TD's.
2010 in Carolina. Deangelo Williams and Jonathan Stewart both don't play in Weeks 10 and 11. 2009 4th round pick aka third stringer Mike Goodson gets the call and posts back to back 100 yard games vs Tampa Bay and Baltimore.
2010 in New England. Former first round pick Maroney is shipped to Denver for a 4th round pick. The Patriots two best RB's all year long are two UDFA's in BJGE and Woodhead.
2010 in Houston. Arian Foster came on strong in the last few games of 09 for Houston after being undrafted free agent. Arguably best RB in the league (stat-wise at least) in 2010.
2010 in Green Bay. James Stark, sixth round pick who was on the PUP and was inactive for most of the year is key in Packers' playoff run, exploding for over 100 yards against the Eagles, and giving the Packers a somewhat respectable ground game.
2010 in Buffalo. Fred Jackson, former UDFA, is Bills best RB with 900+ yards and 5 TD's, while top ten pick from 2010, CJ Spiller, rushes for only 280 yards and 0 TD's.
2010 in NY. Ahmad Bradshaw, 7th round pick, takes over starting job and posts 1200+ yards and 8 TD's. Outplays Brandon Jacobs, who, even himself, was only a 4th round pick.
Those are 8 scenarios in 2010 ALONE where off-the radar guys or mid to late round RB's or undrafted guys came in and were big time difference makers and/or out-performed higher drafted guys.
Guys like Addai, Maroney, Moreno, Beanie Wells, Cadillac Williams, Marshawn Lynch, etc have all "washed out" and were first round picks. Guys like Deangelo Williams have been labeled busts early on and then all of a sudden break out for one huge season.
Even if you are more likely to get consistent production from a top pick (AP, CJ, etc), it comes down to the "value" that BB talks about. Is it really good value to be taking RB's that high when so many of them are up and down from year to year, when so many of them are mid to late round guys or are even undrafted guys? For every Peterson and Chris Johnson, there are guys like Maroney who lose out to UDFA's like BJGE.
I don't know how much more evidence you need to see before you agree that RB is probably the easiest position to replace. There are always plenty of guys available, plenty of guys who come out of nowhere.
2) I agree that NE has never really developed an OLB. I also agree that NE started way too late to start turning over the OLB roster from Vrabel/Willle to now. Considering all the swings and misses in the later rounds, NE certainly could have grabbed a couple OLBs during the 2006-2008 period.
That said, investing a top pick on a guy who has never done the job is very, very risky. Ultimately, there have only been a couple guys since 2007 who have actually been the pass rushers people hoped they would - Matthews, Orakpo and Woodley. For every stud there are 8 Aaron Maybins.
Fans would have been appeased had NE selected Sergio Kindle or Jerry Hughes last year, but would the roster have been better? I think the answer to that is obvious.
I agree that it is a more "risky" type of pick, but with Belichick's "genius" and the way he is lauded for his scouting ability, shouldn't we be very confident in his ability to scout and develop an OLB? You look at Parcells, and he always spent high picks on top flight pass rushers, whether it be Demarcus Ware in Dallas or John Abraham with the Jets.
We heard the same things about the Pats and why they couldn't draft an ILB for years. Finally, they drafted Mayo, and he's been very good. This team greatly needs a pass rushing presence at OLB and spending third round picks on Shawn Crable isn't going to cut it. Most top flight pass rushers are first rounders, whether it be Matthews, Suggs, Merriman (before the injuries), Ware, Orakpo, Mario Williams, Julius Peppers, etc.
I was not a huge fan of either Kindle or Hughes pre-draft in 2010, but I want to give them both a fair shake. I was more of a Hardy/Dunlap/Worilds guy due to their power/size/athleticism.
We have never seen Sergio Kindle on the field in the NFL, so how can we judge what he would have done for the Pats? The kid fractured his skull by falling down the stairs. It's not like he's in prison for murder or anything. Give the guy a chance to heal and we will see what he can do on the field.
Jerry Hughes was stuck behind Freeney and Mathis on the depth chart. Probably one of the best bookend DE tandems currently in the league. Let's see what he does if one of those guys goes down.
3) I've said this before, but it seems those who desire an OLB can't quite grasp it. OLB struggles were way down on the list of causes for NE's atrocious 3rd down defense last year. ILB coverage issues was by far the primary reason. The number of plays where TBC or Warren were bearing down on a QB only to see him calmly toss to a receiver completely uncovered right in front of him vastly outnumbered those where the coverage was solid but the QB had all day to wait for someone to come open.
I disagree with this. While Guyton is not as good in coverage as he's given credit for by many, the pass rush was much more of a problem than the coverage. You're going to have miscommunications and messed up coverages when you've got a lot of young guys on defense, but there were some games where the Pats did not even come close to touching the QB. Mike Wright led the team in sacks and didn't play again for the rest of the season after the Colts game.
Was Mark Sanchez under any pressure in the playoff game? Part of the reason some of the coverage looked so bad and the 3rd down defense was so bad was because of the time QB's had to survey the field. The 4 man rush was simply anemic. Eventually the QB is going to find someone that is open because coverage inevitably breaks down -- you need your DL/LB's to help collapse the pocket and force a throw before the coverage breaks down. The Pats have not been able to that for 3-4 years now.
TBC was a non-factor for a great portion of the year and lost snaps to Ninkovich and Cunningham. Besides the Steelers game, where the Pats blitzed an injury ravaged Steelers OL into oblivion, which game did you really feel the Pats pass rush imposed its will on the opponent? Not often. Even on Thanksgiving, they couldn't get to Shaun Hill and just decided to go with a three man rush and play max coverage. It was a serious problem.