new to IDP, need help please!

I apologize if this is long, I will try to make it as concise as possible.  IDP scoring is: (solo tackle = 1).....(interception/sack = 3).....(forced fumble = 2).....(def TD = 5).....(safety = 5)....(blk kick = 3)

We start 1 defense captain (any player, preferably LB), 1 LB, 1DL, 1DB (out of a 22 man roster)

My IDP are as follows....Kuechly, JPP, Burnett, Washington, Atkins, Barron...starters are kuechly burnett, JPP and not sure who to start as my defensive captain. i drafted atkins to fill in for JPP as he will most likely miss start of season. i was not happy with my draft. i am looking for any help for a solid LB to pickup to plug into my captain spot. is washington bad that i drafted him to sit on bench until his suspension is over? The following are who are taken in my league to make it easier who is left.  Thanks for all help in advanced

LB: washington, von miller, poz, laurinitis, derrick johnson, david, aldon smith, kuechly, greenway, bowman, mayo, freeman, fletcher, wagner, willis, briggs, spencer, dquell jackson, ellerbe, ware

DL: watt, spencer, wake, atkins, charles johnson, ware, hardy, allen, campbell, JPP, peppers,

DB: tillman, burnett, weddle, finnegan, sherman, harper, landry, hall,, mccourty, barron, berry, chancellor

please help me turn my team into something better (kuechly, burnett and JPP were my starters last yr along with aldon smith who i traded...my draft yesterday i drafted washington, atkins and barron, but would appreciate all help and changes to make my team better.  i need a defensive captain (flex), LB, DL, DB and i like to have a backup for each.  

The list of players that you gave......are those who is left or are those who are taken?

not sure why you think the players you have need to be replaced. you have arguably the 3 best players at theyre position.

hey tony, thanks for responding.  They are who are taken in the league, its a small league so it was easier writing down who was taken. i understand my players are good, the starters that is.  what i am looking for is one more starter (the defensive captain or flex position where any defensive player can be used) and my backups.  i like mark barron as my backup DB, but im not too thrilled with washington with his suspension or atkins in place of JPP for start of season. as of right now my starters are kuechly...burnett...atkins...barron (flex) for week 1 because JPP will most likely be out.  is washington a good add for when he comes back? is atkins ok as a fill in for JPP to start season?  i dont want to have to flex barron i would rather flex a LB but i am not sure who is a good sleeper or un drafted player to put in. hope that helps, and thank you for helping me out!

any thoughts on possibly picking up desmond bishop?  can he still be effective in that defense with greenway? he is available.