I don't think my monitor has the best dynamic range in the world, and sometimes I think that it might show darks a little lighter than most other monitors. But it has a Huey attached to it so its actually calibrated.
In my opinion - #1 looks very overexposed. #2 is best as far as exposure and natural color, but looks flat because there's not enough contrast. #3 looks too contrasty and I don't like the colors as well - it might be the difference in contrast that gives it funny colors (I've sometimes seen that when using Lightroom and going by the histogram to boost contrast). #4 has elements I like about it, but over-all it's too dark for my taste. The one thing I do like about it is that it appears sharper - don't know if that's because of the darker contrast or what. Both #1 and 2 look softer than I like.
Which one did you start off with originally?