Remember, she's already admitted to deleting all the emails she didn't turn over, and she also admitted to filtering the emails she did turn over for being "work-related" -- and Benghazi-related at least as I read her attorney's letter. So turning over the server is almost meaningless.
If, by some chance, Hillary didn't actually wipe the physical drives, maybe the data could be recovered, with some IT work. But the odds are that everything politically sensitive and not about Benghazi is gone, and anything about Benghazi that has been left in place is legally kosher, at least in Hillary's eyes, or kosher enough for a Clinton to get away with.
I'm not really optimistic about getting criminal charges out of this whole mess, but the pieces are there if someone is willing to put them together. And I can't help but think that they will go back into pieces as soon as Hillary bows out of the race in favor of Obama's chosen successor.