What are the common mistakes to avoid in character development in fiction?

The Divine Doctor's soul transmigrated into a female-dominated dynasty, where the original owner had an infamous reputation for cruelty and left behind a mess. Her house was empty, the thatched cottage leaked rain, and the grain bin was already bottoming out. Faced with her handsome husband and then glancing at her own homely appearance, she dashed on the grand avenue toward becoming a Steel Teeth Rabbit! Dare to covet her husband? Beat them up, there's nothing that can't be solved with fists! If there is, just keep on beating! Poor? Utilize Medical Skill, fragrances, textiles, fine food, wineries, get into business, open shops, hire workers, but wait a minute... Why does one after another always make a fuss about running away from home? Good, this time she'll be the one to skip out and let him worry, hmph!

She was the celebrated Oiran in her previous life, winning glory throughout the city, only to be betrayed and killed by her sister. When she opened her eyes again, she found herself as a little entertainer who had just been kicked out of a girl group. From then on, she embarked on a journey to lose weight and fiercely battled against the scheming bitches, relying on her wits and bravery. All in all, this is the development diary of a goddess ascending in the showbiz, accompanied by a male lead who appears aloof but harbors a tsundere heart within.

Su Hanyan transmigrates into a novel set in the industrialization period. She becomes a cannon fodder side character - one with a weak personality, who is always being bullied by others and often used as an unlucky sacrificial lamb by the novel's main characters! In the novel, her 'fantastic' mother favors boys over girls. Carrying the mindset of 'sacrificing her daughter's life for the happiness of the family, she is made to give up her job for the female lead and that marks the start of her tragic life. Her family bleeds her dry, just like the female lead. She goes after the same guy as the female lead despite being abused by her husband. It can't be any worse. After recapping the entire story, Su Hanyan tears the script into shreds. There's no way she's going to be cannon fodder! She was never a coward! To deal with these heartless people, she has only one thought. She cannot let them have their way! In two words, f*ck them! Enter the young and talented surgeon, Jin Chen. His looks, capabilities, and family background are top class. He's cold and proud. Many women have tried to woo him but no one has caught his eye. This continues until one day—the usually indifferent Dr. Jin directs his warm and adoring gaze towards a young lady and says, "Anything Yanyan says goes!" Everyone is stunned. How did this random stray from the Su family get you into her hands? "Woo her!" Jin Chen smiles brightly. "I was the one who wooed her. The secret is to be shameless!"

In a group-pampering novel, Nan Qiao was the female supporting character who lost her glamor as the female lead. She was cast aside by her father, her three brothers, her grandparents, and her friends. Her father wanted to cut off all ties with her, her three brothers only adored her stepsister, and her grandparents, who favored boys over girls, also sided with her stepsister from another mother. "Stop trying to tie me down. The person I love is Zhi," Nan Qiao's fiance said. "Nan Qiao, will you stop being so problematic? Your sister saved your life," her father said. "Nan Qiao, I'm very disappointed in you," her eldest brother said. "How could you hit your sister? Don't you know how fragile your sister's body is?" Her second brother asked. "I can't believe you're such a heartless person," her third brother said. "Kick her out. The Nan family won't tolerate such a horrible child!" Her grandparents exclaimed. After reincarnating, Nan Qiao came to her senses. Since none of you want me here, I'll be the first to leave this time. Nan Qiao inherited assets worth billions from her maternal grandfather, and her seven brothers from the maternal side of her family pampered her beyond reason. Her eldest brother was the CEO of a company, her second brother was a famous celebrity, and her third brother was a professor... They fought each other for her attention. Just as Nan Qiao's life was getting better, a top-notch villain in the original novel set his sights on her. Huo Yichen pinched Nan Qiao's chin and squinted a little. There was a cold look in his eyes. "What's the matter? Do you think you can run away after flirting with me?" *** Nan Qiao thought everything that happened in the past would stay in the past, but her family, like her, reincarnated with memories from the previous lifetime. Having tortured her a thousand times over, her family came to her with tears streaming down their faces and begged her to return home. "I'm sorry, Qiao. I made a mistake."

After a long slumber, Zhou Yi wakes up in a wasteland era. He discovers that the new humans, to avoid the daylight supremacy of the Guangna species, only dare to come out at night, meekly whispering in the darkness and scavenging for trash. Exasperated, he questions how humans could have deteriorated to such a state. Lamenting that each generation seems to be worse than the last, Zhou Yi decides to show them the ways of the older generation. Embarking on a quest to transform the wasteland, he aims to rebuild the lost splendor of humanity.

An introverted girl has had enough of the isolation inadvertently formed by her solitary nature. Things changed when she discovers that she has the ability to transverse across the fabric of our universe into the dimensions of multiple storylines. Not only do these storylines leave her with invaluable lessons - they also impart a portion of their power - if she is deserving of it. The time has come for Zhao Youyue to change her fate. Never again, will she remain as a Side-Character!