I just came across the manage character feature. My question is, does the new character benefit My..

It just lets you start a new game in another state. You can't run 2 characters in the same state under the same game (you can start one on another device though)

You can however start a new character in a new state and fly it immediately to a new state, or build it up to level 15 headquarters and then after purchasing a flight ticket, fly it into the same state as your other account if you choose to do so.

You start over. The benefit is you might get plopped into new server, can join new alliance, get away from toxic people, etc.