My own take on the secondary is this:
The same players that some are worried about losing now are the same guys that they complained about lack of playmaking and production just prior to 2016. One good season shouldn't change that, but it apparently has for teams around the league. It seems to me that the league saw one good year and not several mediocre to bad years leading up to it.
What that does for me is to give me more confidence in the quality of coaching the team now has in place. It looked to me like the entire secondary got better across the board, from Claiborne, to Carr, to Church, to Jones, to Heath, even to Wilcox, a player most of us wanted gone and never expected to even make the team. And that quality play also extended to Anthony Brown as well. And while I certainly give the player credit, I think good coaching helped him as well. So, I have faith in that same staff to be able to coach any new players coming in, via free agency and the draft.
And a silver lining to having these needs is the fact that those needs completely align with the deepest strengths of this draft, secondary and pass rusher. So the prospect of good coaching and a strong draft has me more optimistic than pessimistic that not only can these players be replaced, but they can be upgraded.