Five people have their own styles and accomplishments, so it's hard to compete. If we must compare them, according to the evaluation of calligraphers and connoisseurs in past dynasties, Su Huangmi is a class, and Cai Xiang and Song Huizong are slightly inferior. Su Shi, Huang Tingjian and Mi Fei are all peaks and milestones in the history of calligraphy. Perilla is fat and charming, Huang Zi is majestic and solemn, and Mizi is full of enthusiasm. Mifei, in particular, is a peerless master. People who want to write running script are unlikely not to learn from Mi Fei. His followers are the most powerful, and they still are. Cai Xiang's calligraphy has never been highly appraised. Some people say that this Cai should refer to Cai Jing and Cai Jing's handwriting is really good, but he is a traitor, so we don't pursue it. As for Song Huizong and Evonne, his thin gold body is unique, but his meticulous brushwork is not ideal. He also has calligraphy works handed down from generation to generation, such as Fangfang's poems.
If you are a beginner and have no knowledge of calligraphy before, you'd better not give advice from these five people. Because their handwriting is good, but it is not suitable for beginners. Most of Su Huangmi's and Cai's works are cursive, and the thin gold body is not suitable for beginners. Generally speaking, it's better for beginners to practice regular script, starting from Yan He (Chinese script, big script), or starting from Zhong You, Erwang and his son (small script) or Chu Suiliang and Yu Shinan (Chinese script); If you don't want to practice regular script, you can start with official script and look at the inscriptions in Han Li, such as Cao Quanbei, Yiying Monument, Zhang Qianbei and so on. Another option is to start from Weibei. Famous ones such as Zhang Raptors, Zhang Heinv, Cong Baozi, Cong Longyan, etc. are all vast. But most people still start with regular script. As for which one to choose, it's best to look at them all, search for works from the internet, and learn from whoever you like.
If you have a basic knowledge, you can write cursive at the same time, so Song Sijia is a good choice. And, of course, the cursive scripts of the two kings' father and son, Zhang Xu and Huai Su. But then I believe that you have opened your eyes and don't need advice from others.