Haven't had my M-43 more than a few days but it has gotten some use both on wood and cutting hot dogs. I second the recommendation. I personally prefer a lot of belly on my knives, and thus shy away from the WW2 and even BAS and lean towards the M-43 and BDC style, another one to put on your radar. A KLVUK is practically a staple in every collection, honestly I say get one on top of whatever else you get for a heavier blade. Tamang is another great model, straighter profile and somewhere between a "Super-KLVUK" and a beefy machete. Great for trail clearing and such, and will easily tackle big logs.
As far as size and weight goes, you want something in the 16-18" range (overall length) at around 25-35oz, with the exception of the KLVUK, which you want 15", 15oz. Yes that's a pretty broad range, and leaves room for almost every blade "feel" from light and fast to big and beefy, but my point being that pretty much any combo in that range will be a good "everything" knife for SOMEONE.
So now the hard part, decide what models tickle your fancy, and how you would like the blade to feel. Quick examples, a 16" 25oz blade of any model will feel lighter than it's 35oz twin, and an 18" 25oz version will feel even lighter than the first. This blade may even be too light for some if the chopping you'd want it to do. On the other hand, an 18" 35 oz knife will have advantages over a shorter or lighter knife when it comes to chopping, but for me would be too large both to control and to pack for very far.
Obviously I'm touching the tip of the iceberg, but the best way to find out what you like is to hold and use a blade. Hence a nice cheap KLVUK is a good starting point in my opinion.
Summary: First, get a KLVUK. Then also M-43, BDC, and/or Tamang, plus what the others said. Somewhere in the 16-18" and 25-35 oz range should be the where the "butter-zone" is found. I'm about 5'9" and 120lbs, and I've narrowed my butter zone to 16-17" and 24-30oz. My latest, the M-43, is about 17" and 27oz and feels perfect for me, but I'm still concerned about extended use.
Oh one other minor thing to take note of, some models like the KLVUK and Tamang don't typically come with a karda and chakmak. For a true 1 sheath package, I'd recommend a model that comes with those, or else you still need a small fixed blade or folder to accompany the khuk.