I think you will need to think about your trips and where you would like to of had a knife.  I like a knife on my belt and I have used a fillet knife but they do not have a snap on the case so they fall out when I set down.  What I carry now is a small hunting knife on my belt with a snap on the sheath.  I also have a fillet knife in the bottom of my tackle box. You may want to look for something you would use while not on a canoe trip. When not on trips I carry a small 3 blade pocket knife.  Maybe a kitchen tool.