Since I'm not well - versed in Yuta Tanaka's light novels specifically, it's hard to say for sure. But in general, light novels often have simple yet engaging language, vivid characters, and unique story settings. His works might also follow these trends.
Maki in fanfiction usually has a fierce loyalty to her friends, especially Yuta. She is the type to fight for what she believes in. Yuta is sometimes portrayed as being a bit naive in the ways of the world outside his own small circle, but his pure heart makes him endearing. In many stories, their different personalities create an interesting dynamic, like in a story where Maki's boldness gets them into a risky situation and Yuta's calm thinking gets them out.
The 'jjk colored manga' quality is a mixed bag. It could have excellent color schemes that bring the characters to life, or it might have inconsistent coloring that detracts from the overall look. It really depends on the specific edition or version you come across.