Originally posted by Bad Boy Rather than upgrading your body seriously consider investing in better lenses. You will see more improvement in your photography upgrading your lenses.
I tend to agree with the above. If you're not using the K-3 much, it would seem an upgrade body wouldn't change that much. I'm still a K-3II user, and although I'm waiting for my K-3III to be delivered, if that new body hadn't been release by Pentax, I would still be happy with the K-3II, which is not very different from the original K-3. Actually it's pretty much the same in terms of IQ. There are so many thing to discover in these old bodies, esp with a new lens. E.g. if you only have a zoom lens, why not try a small DA limited to reduce the bulk of your camera, and take it out a bit more because of that. Having a limited field-of-view will make you consider framing more carefully and greatly improve your photography. Also, follow a few photographers on social media to get new ideas, ...
Getting a new body is not the way to improve your photography, except if it has features that you are explicitly looking for.