Honestly...
I think Cam Smith and Bonner will have a camp war to win that spot. Remember... despite going undrafted, a LOT of draft scouts thought Bonner had a real shot to make it in the NFL. We gave him a big signing bonus (for an UDFA) to get him to sign with us... and he looked pretty good in limited action.
Smith has a better athletic profile though, and if the light comes on... look out, a lot of folks thought he might creep into the first round.
Ramsey is clearly our CB1, and Kohou is a talented slot corner, (just not fit for boundary work). I think we'll be better than some here believe. If Needham returns to the team, and to his pre-Achillese injury form, he'll press Kohou for that spot.
I think we've got enough at CB, and other than another late-round project (which we should do EVERY year), I think we'll be okay. Fine, even.