Here's the deal...since knives are the backbone tools to the culinary trade...before you go out and spend a great deal on quality knives...continue to do your research. Your doing great. Off the bat brands such as Wusthoff, Henchels, Shun, Viking...etc. are top quality. However, more than top quality...everything comes down to the user and ultimately their knife skills. In Western cooking, chefs use a large variety of specific knives. In Asian cooking (I'm talking about Chinese cooking) their approach is mastering mostly just one knife/cutlery tool: The Chinese cleaver. Once trained, there is pretty much nothing you can't do by mastering a Chinese cleaver: Mortar/pestle, dice, mince, chop, butcher, fillet, pound, tenderize, slice, debone, pulverize (with the side...as in smashing garlic cloves). So, all that being said, I would say the things you need to keep in mind are:
-Weight & balance
-Feel (ergonomic "flow") -How does if feel in your hand? If you would be using it for a long period of time, is it comfortable for the size of your hand? How would the handle feel should your hands become wet?
-Materials: High carbon stainless steel, hardwoods on the handle
-Design: #1 rule in most kitchens...Does the "tang" go all the way through the knife handle? If you don't know what the tang is...it is the very very end of the knife blade opposite the tip. This is what the "blacksmith" would be holding onto as it's tempererd/seasoned in the fire during the forging process. A cheap knife indicates that the knife blade is stuck into the handle (minimal length). A quality knife will find the tang extending the entire length of the knife handle, enclosed with quality reinforeced rivets.
*Cheap knives are great for sales people...you'll keep selling the forever...the cook will replace them over and over". Like most things in life...quality lasts...so find the quality set you need. Tallk to working chefs about their approach to knives. Final tip: If you find a quality knife...do your research and see if you can find what is called "Open Stock". At some high end Dept. stores, they offer open stock sales. Ex: a $200 Chefs knife might be reduced by $50/$100 just because it was opened and on display. It's a real score when you can find stuff like that.