Kyle's scheme and playcalling.
When RGIII starts slipping a bit, or Kyle calls a less than stellar game, then you see how (not) good our WRs are. They are not that talented. Sure the WR position tends to develop slow, and guys like Hank and Aldrick have their strengths. But our WRs have had chances to make big plays, and have not done it. A star-quality WR catches that deep ball from RGIII yesterday. A star-quality TE catches up to that ball RGIII slightly overthrew (Davis catches that for 50 yards imo). A star quality WR finds a way to haul that pass Robinson dropped, armbar and all. The ball hit him in his body.
Looking at their catch rate is misleading. What kind of catches are they being given the opportunity to make? Kyle has been running a quick strike, short-intermediate passing game, and has a very accurate short-intermediate thrower throwing to them. They're not being asked to make big plays down the field - why? RGIII is one of the best deep-ball prospects the game has ever seen. Could it be that our WRs outside Moss are that bad at converting big-play opportunities?
I think if I were an NFL GM, I'd be thinking about whether he's too young to be my head coach of the future.
Furthermore, investing in the secondary (unless secondary is BPA) has it's own problems - our defense is the way it is because it is coached horrendously. Yes, there are real talent issues, but the offense has real talent issues. It's a top 10 unit in the NFL still last I checked. A great defensive mind can overcome talent issues, or at least mitigate them. Imagine the Jets with someone other than Rex Ryan coaching them - it's not pretty. That unit is so depleted yet they're still middle of the pack. So adding secondary talent would seem to have diminishing returns (getting an awful unit to be an average unit) seeing you could do the same thing by just changing coordinators, while adding offensive talent would propel us to Saints/Patriots/Packers territory offensively.
Also it's so hard to find impact DBs at the moment; how many truly impact CBs are there right now? How many truly impact safeties? And can you project any of the talent available at our pick to be "impact"? I can fairly safely project Craig Ertz, Monte Ball, Oday Aboushi, Jake Matthews, Cordarelle Patterson, Tyler Eifert, among others, to be impact players, or at least more safely than I can project Carrington Byndom or Matt Elam.