Very good Question I agree with you on the 4 different styles of fixedblades and like bigocean pointed out you need a folder and I would say a Multi-tool as well (old school leatherman supertool for me) now dose that mean a "compleat collection" NO. if it did you would have no reason to buy more knives. So that may be a complet collection of "using knives", but you gotta have more than that. The whole point of a collection is that it is always growing with your whims, wants, and what the Yard has for sale also I think it is important to be expanding in to new areanas of knife, Just my 0.02.