I worked at the Harris Nuclear plant in New Hill, Nort Carolina for 28 years. My second novel HARRIS was based on that facility. Many of the details about the plant and characters in the novel were real. I changed certain security related items for obvious reasons.
The bad ones (very rare), especially a 1-star with no written review, used to bother me. If you're going to trash my writing at least tell me why. The good reviews are are like a beautiful spring day. they make me smile. In the end, you have to let them all go and keep writing.
I create my own covers using Powerpoint. They always tell part of the story inside. You can create multiple layers and overlay the images and text. I try to keep my titles simple.
I run all my writing by my wife, especially female characters, which I have a lot of. Depth, vulnerability, and power. My first female character was Amanda Langford, 5'3", 100 lbs, southern, nuclear engineer, just trying to find a job. the CIA wanted a specilist who knew radiation and read Chinese. What she found shook the planet . . . literally. Vulnerable, insecure, determined, sensitive, and in the end the hero of my first six novels.