Hmm...
This is just my opinion, but it is based on my experience.
One knife will not do all things well. One knife can be pressed into service to perform all functions, but it is often at a price.
A person needs a battery of knives, not just one. The settlers, longhunters, mountain-men and their ilk carried a battery of knives because they knew from experience that a camp knife makes a poor patch knife and a patch knife makes a poor fighter.
I am not going to touch much on "fighting" or "tactical" knives, as I have little experience with them. I will leave that subject to others. If I had to choose one, It would be a Bagwell Bowie of sorts or a > 8" broad bladed dagger with plenty of distal taper.
Here is my outdoor battery that I have been satisfied with for years.
Pocketknife: Swiss Army Tinker. This will get used alot. (~$20, I have not priced them in awhile...)
Light/Medium Duty: A Scandinavian Style fixed Blade, 3-4" in length. I have many, but I find myself using a battered Brusletto or a cheap Mora more than any other. This blade sees more use than any other in my battery, and I find it to be very adaptable. It can do things a Big knife can, but the opposite is not always true. (anywhere from $7 to several hundred, the cheap ones are just as good, just not as pretty.)
Heavy Duty/Camp knife: Again, I have several that fill this niche, not the least of which is the aforementioned Ka-Bar. I would not hesitate to reccomend one of these. Another good one (from what I hear, I have not tried one yet myself) is the Becker line of knives. I have also heard wonderful things about "Swamp-Rat" knives. (Ka-Bars and Beckers both run around $40-60 depending on model and where you get them)
With your budget, you can afford one heck of a good battery of knives. I doubt that you will find a "one knife" that will do everything, from killing gobblins to chip carving a spoon for eating, or whittlin out a figure 4 trigger for a trap at any price.
With $100 you can get a world class battery of blades that will do everything that knives need to do in the outdoors and indoors. Any extra money you spend on bells and whilstles is just "gravy" as they say.
As I said before JMO.
Oh yhea, don't forget sharpening equipment...