What about government commercial negotiation information, surely the government can (should!) keep that secret at least until the negotiations are over, otherwise every single purchase made will have them ripped off due to information asymmetry.
Troop locations are another one. If you know exactly where everything is it gives you a huge advantage, and to a lesser extent where they've been.
Surely there are some secrets we can acknowledge the government can keep, for a time. The problem only arises when the executive branch abuse the classification system and label embarassing, non-sensitive (to the country, maybe not to their reelection) information as sensitive information.