I think anytime you have two very good starters at a position it's hard to call it a huge 'need.' Similar to WR. But CB would obviously make sense if the value is there somewhere. And I could see that possibly being as high as 57 overall. Who knows.
Burgess can play slot- as Johnson did sometimes this year. And maybe Long can take over as the CB3. But then, maybe not. And maybe Morris will prefer to use Burgess as more of a pure strong safety. Plus it is true that nothing is guaranteed with Williams beyond this year. So grabbing a CB next month could be a good move.