This should be easy right? We have Brian Cushing and Demeco Ryans, it should be one of the few positions on the defense with no real competition during camp. That could be true if both were healthy and playing the same positions from a year ago. But there's no guaranty that Ryans will be ready at the start of the season or that either of them will adjust well to playing 3-4 ILB.
With that said, here's how I see the position breaking down and how I think it'll all pan out. It may not be popular, it may not be pretty, it may not be the most intelligent opinion out there... but well honestly what else do you expect from someone lacking in all of those qualities himself?(Weak inside linebacker): Probably the LB that's going to be in coverage the most, so obviously cover skills would be nice. He'll also need to be able to crash the line and take on blockers but not near as much as the SILB. In the 3-4 ILBs don't have to cover as much ground as the MLB does in a 4-3, so it's ok if he's not the fastest guy in the world, but he absolutely needs good short area quickness....
Demeco Ryans: I was worried about how he'd fit in a 3-4 whenever anyone mentioned anything about a scheme change for years. Even if he could come in 100% healthy at the start of the season, he's probably the linebacker I have the most questions about coming in. He's ok in coverage but not exceptional. He's not the quickest, strongest, or fastest of LBs in the NFL, and honestly I think he'd be better as an undersized SILB than WILB. With that said, he's still a fantastic player and has the ability to be a quality 3-4 ILB, i'm just not sure it's the best position for him personally and that it won't show on film when the season does get here.
Zac Diles: Diles was a very versatile 4-3 LB being able to play pretty much all 3 positions, in the 3-4 though he's probably going to be limited to WILB simply because he doesn't have the strength to play SILB and isn't a good enough pass rusher to play outside. Honestly I think Diles would provide good competition with Ryans for the starting job even if Ryans were 100% healthy... I think Ryans could still win out over Diles, but I hope they open the position up, those two guys could really push eachother making themselves the better for doing it. That's also assuming Diles is even with the Texans next season...
Xavier Adibi: Adibi has the physical toolset to be an outstanding WILB, except for the small fact that he couldn't cover grandma with a walker... He's probably nothing more than deep depth/special teamer
Kevin Bently: Bently might be in the running simply because Ryans is unhealthy, Diles isn't on the team and Adibi is well, Adibi.
(Strong Inside Linebacker)- This position is designated for the "thumper" at linbebacker, the guy who's maybe not the quickest and most agile, but will crash the line and punish ball carriers. Strength, Strength, and more Strength is what this position requires...
Brian Cushing: Some question whether Cushing won't suffer from moving inside because he didn't look the best at MLB with little practice time at the position. Personally, I think Cushing is better suited for 3-4 SILB than he is a 4-3 OLB. He's going to be asked to read gaps and fly in and make plays... that's right up his ally. He won't have as many responsibilities as he did at 4-3 MLB. He'll have to cover some, but Cushing is really pretty good in coverage for the position.
Darryl Sharpton: I absolutely love Sharpton at SILB, I wouldn't give him any real shot of beating out Cushing.., but I think he'll provide very good depth at the position. He reminds me of a Sam Mills, another guy everyone called undersized, but his short stature actually made him harder to block in ways. Sharpton also seems to have pretty good instincts for such a young player, I really, REALLY like him as a 3-4 ILB.
My predictions for the starting lineup next season? Well, I don't think it'll happen in a million years, but if it were me i'd play Cushing at WILB as he has adequate coverage ability for the position and Darryl Sharpton at SILB... the middle of the field would be no mans land for the running game.