Once you get your hit points up a bit you will probably need to put more into agility than constitution. I found it better not to neglect speed and survival, though others have made successful builds with either high strength or agility (don't recall the details, though).
I described my early stat distribution in the topic
Killing Fergus.
Early in the game skills are relatively cheap to unlearn, so you may want to invest a couple skill points into your weapon expertise of choice, even if you are planning on switching weapon types eventually. If you are not having combat problems, though, the extra skill damage or accuracy (etc) are not essential.
