I worked in a knife store for 15 months and came to a similar conclusion.

Since I am a compulsive kind of guy, I examined the knives I did not like and tried to figure out why. My conclusion was that a liner lock seemed to be the easiest style to do badly. And maybe how they fit my hand.

Having said that, there were some manufacturers that seemed to do a good job, at least it was good six years ago. Two I remember are Lone Wolf and the Al Mar SERE. And the framelock Sebenza.