Right now, there are big, bad, heavy Spydies with lockbacks, and there are lighter Spydies with linerlocks or compression locks. How about a big, bad, heavy Spydie with a compression lock?
The heavy ones seem to be heavy because of sturdy double steel liners, whereas the light ones have partial nested liners or no liners. So what I'm talking about is a hefty, tanklike Spydie with dual steel liners but a smooth-opening compression lock. I'm not suggesting that this be done to the Chinook--the stiff lockback is part of its character--but it could be a good recipe for a mini-Manix or something along those lines.
There are plenty of lightweight lockbacks too, so it seems like the only missing combo is a big ol' brick of a knife with a compression lock. (The ATR doesn't really fit any of these categories, I think.)