Also it be sweet if Rainbow fought zero for her personal needs but for others. She knows Twylight hurt the CMC, blackmail Fluttershy’s to help in the Marer Do Well and Walking Dead hoaxes as well as in the Bird in the Hoof error, try to Rob Queen Novo to save her rep, neglect the humans including the twins, and risk many by causing the ‘student’s on the Marer Do hoax. And also found out she hurt Daring Do through her guilt on leaving her family including Rainbow’s mother who’s her sister. So Rainbow fought to protect her read ones. Even if she refuses the crown, she only wants to protect her dears. And when many see for her execution, she replied how her shame be a more fitting punishment for her hypocrisy.

It rock if some worshippers of Rainbow for her heroic acts in dimensional wars set this to show why Rainbow’s more worthy to lead than Twylight. Why? Stronger; physically, mentally, and spiritually. They see Twylight as a betrayer for her sins such as the Marer Do Well and Walking Dead hoaxes as well as the cheerleading and swamp incidents and betraying the CMC and prejurdicing outsiders including Capper and Dyscord. And also her insanity and conceit. Hence the Trial by Fighting to ensure Rainbow is leader.

I wish this happen.
In my headcannon, Rainbow uses martial arts similar to those from China, Japan, Korea, Siam, India, the Phyllipines, Indonesia, France, and more. Approve better than Twylight.