Every knife is a compromise. I have yet to find one that is "perfect", and I do not expect to: my goal is to experience different kinds of knives.
LOL! Lighter would be nice, I hope it don't hinder the strength of handle or use.I (like most guys I know) really like flashlights. I found a nice SOG folding lockback knife with a pretty powerful LED light on it. It is one of the knives that I take when I travel (by car).
Other than a pocket clip, I do not needs gadgets or gizmos on my knife as I almost always have a multi-tool and/or a SAK on me as well.
So, a good blade shape, decent edge holding along with relative ease of sharpening, good ergonomics, a well thought out and well executed clip, good ergonomics, a reasonable price and a rock-solid warranty from a good company that will be around and honor it.
corkscrew, bottle opener, a hex bolt opener, a file, a saw back, mini hidden compartment etc.
Whats it, that make it perfect.