How about a search facility that finds things like MX-1 ?

Aliengrove's comment was actually made last November whereas DXO's K-3 modules were only published last week (15 Jan) so the processing of that image was not made with their optimised K-3 noise reduction. Perhaps he could update his DXO to make a comparison now?

Multi-segment metering should provide the optimum exposure range, albeit not necessarily at the best level for the subject. It should preserve shadow details and prevent highlights getting blown so you end up with an image that can be easily worked on in post processing. However almost always the photograph will need working on to obtain the optimum levels for the subject matter.

If anyone wishes to know, Optic Pro 9 now has full support for the K-3 (since a week ago.)

Your uploads have worked just fine.
I agree the colour curves of those look on the low side, albeit they are recoverable. Did you take in camera jpegs as well otherwise it's still hard to say whether it is an issue with the images or the raw processing. I would think it should be possible to produce very acceptable images from your raw files as even from these jpegs the detail is there.
As here:

Windows Live Movie Maker can read K3 video files, allow some basic editing and burn to DVD. Not the most intuitive of editing programs, but it is free.

Can you upload one or two - it should help to see what the issue is. Sometimes the exposure the camera gives is not necessarily the best setting. An obvious example is a snow scene which will be made to look quite grey by an automatic exposure system. In that case the exposure would need increasing to compensate and it could be something similar affecting your landscapes. Similarly a dark subject might be lightened too much by the auto exposure so the exposure would need decreasing to make it better represent the subject. That's not just a Pentax or K-3 issue but affects all cameras using automatic exposure.

The multi-segment takes the brightest and darkest parts of the scene to determine the exposure - just maybe the subject in your photo is not best metered by that method. Some who take landscapes use graduated filers to reduce the overall contrast range.

Given the K-3 gives you an instant review of the photo, it should be possible to retake it if the result you're seeing isn't what you want. Also a tweak in PostProcessing, eg Photoshop Elements may help bring the image to what you expect.

Which method of metering are you using and on what subjects?

Anything here to help?
https://helpx.adobe.com/photoshop-elements.html

Then there are many Youtube videos and other sites showing how to do things with it.

The MX-1's articulated screen allows the use the camera to be held against the waist like you may have done with a Box Brownie or perhaps something more sophisticated such as a TLR Rollei etc. which allows framing to be more precise than holding the camera shakily at arms length and being unable to see what's in the viewfinder because of the reflected sunlight! It makes a pretty good quality carry any time camera at a competitive price compared to the Fuji offerings.