Dear CDR Glock,
I don't have a lot of personal preferences about blade sizes, styles, shapes or lengths. the knife should be what you like and what you will carry comfortably which means you will always have it on you.
Auto knives are sometimes complicated mechanisms and assemblies. More parts = more things to go wrong. I am not big on OTF autos. If you get one, get a side opener.
Ernest R. Emerson