Boy Boy...just one Spyderco?? Well personally I don't think that's realistic. I believe any knifeperson will fall in love and then get another, and then another, and then another, because they are all superbly designed, made with excellent materials, and have world class Fit and Finish. They are not traditional looking but usually have simply crazy good ergonomics.
I've got more than just several Spydercos but I'm not collecting. Every one I purchased (some new and some 2nd hand) were meant to be used and carried. They all currently resided in my EDC box awaiting their turn in the pocket.
I personally love the G10 FFG VG10 Endura and it was the FIRST. I feel the mid-lock is a better design so my interests have leaned toward Spyderco's with this lockup system. I also feel that a FFG blade is the best slicer option and for me knives are for slicing (not hacking down tree limbs). I prefer full liners for strength. Finially, any of the premium steels are great. I really like both S30V and VG10 as they are both relatively easy to sharpen and hold an excellent edge. Sypderso G10 is my first choice in handle material just because I like it (FRN is a great choice with liners due to lightness and outstanding durability).
You gave a $100 limit but I sense that you'll go higher for the right knife. I'm going to give my four favorites in order of preference.
1. Foliage Green G10 Endura IV - wins in the only one question due to excellent ergo, materials, midlock, and longer slicing blade. It also has a strong tip.
OR, the Mini-Manix simply and awsome knife and a great hard use knife but not to big. It is a beast of a knife in FFG, S30V. I have a lot of confidence with this one when I really have to bear down to cut something.
OR, the ParaMilitary is very very light. I love everything about it except the locking system (not that there is anything wrong with it, I just can't used to it) and the fact I think the blade is too short. That said it is a cutting machine and the G10 handle's ergonomics are flipping incredible.
2. Native IV, call it the little guy and it has been in my pocket bobbing around with the change since the day I got it and sees the most daily cutting work. So this is my choice for pocket carry but the Caly III gets an honorable mention and is my Native's backup for pocket duty.
My current EDC profile is the Native IV in my front pocket and I'm rotating a Mini Manix, Para, CF Stretch, G10 Endura for back pocket clipped carry. But, the mini-manix is seeing the most clip carry of late. Oh, and most of the time I belt carry a G10/BG42 Buck 110 Folder too.
The EDC box...full isn't it?