I would join because of the need for a refreshing change.
There are good reasons to start a new party and this impeachment trial is good at making it clear.
1) Set it up to scare Rino Republicans into doing the right thing—If they do not support Trump—they will be primaried and voted out by the new party.
2) Set it up as a place for the disenfranchised Americans—a party with real ideals and goals—NOT just Pro-Trump but Pro-American. A party that can run Local elections. A Grass Roots party. Change from the bottom up.
3) a Party to REPLACE the Republicans, not just be a third wheel. America First—Not China.
4) Trump and a handful of Ex-Tea Party People could do this. A Law and Order Party to shape and mold public opinion.
5) BUT the foundation must be set! A) Need a Media outlet because the Anti-Trump Media will brand it Fascist, Racist, Homophobic, Fools, Nazis and Conmen. B) It will need a set of ideals that are universally understood and liked by a majority of people—such as Anti-Late Term Abortion, Love of country, Free Speech etc... C) It must have a solid religious base. D) It must have all the symbols in place like, a Party mascot animal (Lion?) a Party Motto (MAGA) a party Flag (Something from Revolutionary war?) A Color and symbol. It must look and feel like a real party.
It must start small and grow to become a major player fast. With Trump behind it—this could be done.