I think any of these would be good choices. The ones I've owned, at one point or another, are marked with an asterisk (*)
Spyderco (2.5 or less): These would be my favorites!
Navigator*
Navigator II*
Dragonfly (SS* & FRN*)
Meercat
Salsa (Ti* & Al)
Dodo*
Poliwog
Co-Pilot*
Spur
Executive*
Walker (lgtwgt*, Crbnfbr, & Almite)
Cricket
Mouse
Toad
Jester
Ladybug
Spydercos w/ 2.5 inch cutting edges (but the choil adds length to the total blade):
Scorpius*
Native*
Kershaw (2.5 or less):
Mini Mojo (assisted opening)
Baby Boa (assisted opening)
Chive* (assisted opening)
Scallion (assisted opening)
SOG (2.5 or less):
Twitch I* (assisted opening)
Blink (assisted opening)
Al Mar (2.5 or less):
SLB*
Havanna Clipper* (a lot like the SLB)
I hope this helps.
Best wishes,
3Guardsmen