I think I solved my problem with slow processing of images on my older computer. I switched from processing raw files to using jpegs out of the camera. Processing the jpegs a little on the computer is much faster than processing raw files. The jpegs also take up less memory for storage on my computer.
To get jpeg files that I like with my Pentax KP took a little bit of effort. I did something I have not done before. I made adjustments to the in-camera processing of jpegs. I started with the Pentax natural setting and then did some custom adjustments to the camera in terms of sharpness and contrast. I also turned off all noise reduction and dynamic range adjustments.
Using the Pentax KP is now simpler. It creates better image quality. The price beats needing to buy a new computer or camera immediately, but I’ll likely buy a new computer eventually. The only issue remaining is that the auto WB on the camera isn’t as good as some other cameras. I’ll still have to tweak that for mixed indoor lighting situations, but as long as I’m not using the Pentax for indoor Homewood images it isn’t a problem. But B&W images work even better.