What makes a knife appealing varies.. many want plain, some "cool", some tacticool, whatever floats your boat. If you simply play with or show off your knives, if you actually use your knives...all plays a part. Example; for me, design is everything. How it works/cuts, how it fits in your hand, how naturally it opens and closes. I've yet to handle a knife that works as well as the Spyder Hole. Flick it, open it slowly, it works. All of that is the first thing I look for, then how it looks.
I own at least one of most major brands, but the vast majority are Spyderco. They just plain work. THAT makes them attractive to my eye. Thats not to say I will pass one up that just plain goes over the top, rock lobster for example. Just can't dig that one. BM 940. While it may be a good cutter, that reverse tanto skinny blade and slippery handle? Nope. Go figure. To each his own.