Set your camera to AV, take every picture with your aperture at F4, 5.6 11 and 22 if you have enough light. Use ISO 100 in bright light, 400 in medium light and 800-1600 in low light. Chimp your images with the histogram turned on, use the EV button to centre your histograms.
If you can systematically get a handle on the above, and learn to use the controls involved, you have 90% of photography covered. Your K-x is the perfect camera to do it on. I have one myself, I don't use it much anymore, even though it used to get used every day., but I haven't been able to part with it either.
If you aren't doing the above, you probably don't need a DSLR. So either do the above and get on with it, or sell your K-x and look at a bridge camera or point and shoot. Really, if you make a concentrated effort to do these things for a couple weeks, you'll have your situation under control. and if you do decide on another DSLR, it will be an informed decision made with the help of your understanding of your K-x.
Last edited by normhead; 02-19-2014 at 08:48 AM.