Being active duty military and having been on humanitarian relief efforts and field training exercises, if I had to go with Spyderco folders only, I'd go with...
Primary Folder: A Spyderco Military PE, preferably in the high grade stainless steels (CPM S30V or BF 42), or a full-size, original Spyderco Manix PE (CPM S30V). The Spyderco Manix 2 PE (either 154CM or CPM S90V) would suffice if you can't get a full-size Manix. I, personally, wouldn't go with anything smaller than a Spyderco Para-Military PE in CPM S30V as my main folder. These
s offer you practical lengths for a large folder as well as durability and reliability. I've carried the Military, Manix, and Para-Military in very hot, humid conditions in the LRP of my BDUs where the blades would become heavily beaded in sweat and the G-10 handles soaked. I'd simply wipe down the blades occasionally and allow the knives to air out in the open when I went to bed. So far, no rust issues.
Secondary Folders: The Spyderco Delica 4 FRN (or any of the Delica models), VG-10, in both PE and SE. This gives you a smaller PE blade to work with as well as a SE blade should you need it. The Delica's size and FRN handles makes it very practical in carry and expense to EDC in both PE and SE. Your BDUs, ABUs, ACUs, etc., has plenty of pockets for storing something the size of a Delica. Again, occasionally wipe the sweat from the blade and let it air out when possible.
I advocate more for PE in real world contingency situations due to the ease of sharpening no matter what your method of putting on an edge. I also push for a knife dedicated to one thing, hence the recommendation for the Delica in both PE and SE. The Delica SE should take care of your serrated blade needs. If you have to go with a CE edge configuration, fine... I feel you'd be better served keeping it simple and having one PE blade and one SE blade.
Again, my above recommendations work for me when I've had to go out into "the field." Ultimately, consider having a primary folder (preferably PE for ease of sharpening and of a good quality stainless steel) and two secondary folders (one PE and one SE, small, easy to carry, and of a quality stainless steel). CPM D2 would be a good choice, but you may potentially run into rust issues. If rust is not a concern for you, go for it.
Hope this helps. Take care over there!