I own a RAT-3 (by Ontario), an OD RC Izula and a RC-5 ESEE (bka SERE) The Ontario and the ESEE are both partially serrated. Most people prefer plain edged knives for the outdoors, but the serrations can be useful at times. They don't really get in the way all that much, but I would recommend the plain edge unless you really want them.
For your purposes, I would recommend the 4. You don't need a large knife for what you are wanting to do. A 4" edge will do just about all the wilderness tasks you can think of (except chop or baton thick wood). I love my 5, but it is a big knife. Oftentimes, with big knives
RC knives are a little pricey, but not as bad as some other brands. You can get decent deals if you shop around.RC knives are working tools and are backed by the best warranty in the industry. If you really like the design, but ca't afford the coin, the Ontario RAT designed knives would make a good option for you. They are decent quality. and a good value for the money.
It sounds like you want a rough use knife. If that is the case, go with a RAT or RC. If you don't need a rough use knife, take a look at a carbon Mora Clipper.