He's still under contract no matter what, meaning that he should be able to provide a backup/depth role if needed. If we can improve on the position that much to release him and move on, that's great too.
While the safety status surely needs addressing as one of the top positions on the team this offseason, it's not quite as bad as you're making it out to be either.
1.McCourty---clearly our best safety, and if the rumors are true that Belichick and the staff preferred him there all last summer, he should be able to possibly take another step forward with more practice time and experience.
2. OUR BIGGEST NEED (arguably) SS---with plenty of good FA's available and a deep safety class, this could be corrected even if it's a draftee who isn't initially starting until 6 or so games in. A high draft pick would be great, but I'd love a FA signing who is experienced even more. That may actually be the best way to go, especially since Wilson was a high round 2 pick last year.
3. Gregory (or Wilson)---He looked downright lost at times in the beginning, but in the same vein it was just a week ago where many here lauded his TE coverage in the HOU playoff game. He certainly made progress as the year went on, and while none of us want to see him starting again, he's under contract and can provide valuable backup experience at an affordable cost.
4. Wilson (or Gregory)---our high 2nd round pick for the future last year. He looked out of place at times in a starting role early on, but he also showed a knack for the ball too, and many were excited for his potential for the future. He is in the developmental stages still, but was given valuable reps during his rookie season which should help. Again, he's part of next year's team no matter how you look at it.
So, in all actuality, we are really a nice FA signing or a draft pick (maybe both) from not having nearly as big of a weakness as you see.
THE BIGGEST FACTORS
Chung and Gregory will not be starting. McCourty will be at FS for the duration of the year. We will continue the progression of Wilson as a high pick who's been given reps at different roles, and both he and Gregory will be in backup support/role bits. We can continue to add depth if both a FA/draft pick are chosen, not to mention all of the other various ways to improve upon the position.
It's obviously not ideal, but a nice draft pick and/or a bigger FA signing (which would not necessarily break the bank) would be a HUGE step in a positive direction. I'm not saying that solves everything, but it's a damn good start.
I think that one of our bigger FA needs this year, if not the biggest, is signing one of those guys who can immediately step in and add to the progression of the secondary.