This is the subject I come back to often when buying or planning to buy a knife or other outdoors related gear. What it comes down to is what you see yourself using it for day to day, as well as things you doubt you'll need to do, but would like to be able to do should things go that way. For me, when it comes to knives the emphasis is on raw cutting ability, especially on anything smaller than 4 inches in blade length. I divide my knives into categories when it comes to the outdoors.
1. Pocket knives. EDC folders, SAKs and very small fixed blades.
2. Main fixed blade. A fixed blade with a cutting edge between 3 and 6 inches.
3. Choppers. Axes, hatchets, khukuris, fixed blades exceeding category 2 and so forth.
Category 1 is always with me. A robust lockback from Buck or Spyderco and / or a SAK. Usually something like a Byrd Cara Cara and a Vic Farmer. In warmer seasons I generally don't bring any other knives unless I'm testing them for whatever purpose.
The main fixed blade is the knife I use most often. Breaking apart some wood to inspect the insides, cutting some vegetation or small branches, whittling tools and making shavings, slicing up animals etc. The emphasis here is raw cutting power, but I do like a little versatility. I like to be able to dig with the tip, pry off sections of wood and do a little batoning. For this type of use I find a Mora can sometimes be a bit thin, so I usually go with a puukko that's slightly thicker. Any knife along these lines will do. Things I keep in mind with this category.....
-How well the knife cuts. The out of box grind is important to me, because I don't like spending hours re-profiling just to make a knife acceptable in this area. Scandi grinds are usually a safe bet in my experience, which is one reason I favor puukkos.
-Ergonomics. Will it be comfortable to whittle with for half an hour at a time? Again I choose puukko style knives because their handles are usually more round and fat than modern American knives.
-Weight. The lighter the better.
-Ruggedness. How easily does it resist the elements? Are there any small areas where dirt and water will get trapped? If it chips or bends how easily can you repair it in the field? How far can you take it outside of your intended scope of use and have it survive?
-Sheath. Needs to hold the knife securely, needs to be comfortable and secure on the belt and be unobtrusive to carry. Extra points for things like an inability to retain moisture, compartments for extra gear and a design that lends itself to comfortable pocket carry.
As you can see I put the most focus on my main fixed blade. Ideally I can do everything I need a knife for with it year round. The only thing I have troubles with is securing dry wood at certain times and constructing shelters. Currently everything is covered in snow and frozen, and a chopper can make the work many times quicker. Same with constructing a shelter if I'm going to need to break apart wood instead of simply locate it and arrange it in some sort of frame. The choppers are only used in winter for the most part. I have a Khukuri, hatchet and some large fixed blades for this type of work.
To me, if you don't foresee yourself needing to break apart wood for fire and shelter, you should look past thick, long blades and stick to the more focused precision cutting tools. Something like a Mora should work well here. If you want something a little more robust, consider the many different puukkos out there. I have two I really like, one with a 3 5/8 inch blade and the other has a blade around 5.5 inches. The smaller one is thicker in the blade than a Mora, so I can use it for digging, prying and batoning I sometimes do without carrying around a heavy, bulky package. This knife will easily ride in my jeans pocket and works real well in a coat pocket. The large knife I feel is a good do everything knife. It's balanced just a little too forward for it to be as comfortable for long whittling sessions and the weight will fatigue you quicker for this type of work, but it can baton bigger pieces of wood, has much more versatility when it comes to chopping and bridges the gap between category 2 and 3 very well for me. However, a Mora feels weightless compared to it and will be easier on me in extended cutting sessions. So if I don't need that extra weight and length, I don't carry it. Neither should you. Figure out what you need and buy blades that fit your criteria. Sometimes if the weather has been bad I won't even feel like making a fire if I don't have a khukuri or axe with me, other times I've gone into the woods with nothing but a Vic Classic and made all the fires I needed. Weather plays a big role.
