I wish you well with your endeavor; however, there is definite signs that things are not going as well as you believe. Those bettas with stripes are under extreme stress. And if the cause of their stress isn't eliminated they may not survive for long.
Some bettas simply have a low tollerance and are affected more easily.
The stripes should have disappeared, they remain because of the sorority or some other stressor. Give them a week though to calm down, if they persist after that then there may be a problem. So far, it looks to be going ok. It isn't the first few days you need to be wary of, it's more the days after when they settle in and start realizing who's who and where they are and so on. The tank looks great btw.
Thanks, Soltarian. I do understand as time goes by it can become more tedious. I'm all aware of the makes and brakes that can become. I keep a close eye on them quite often.
I was prepared to get some disagreements and some that support. Either way, I wouldn't ever let any fish of any kind in my house get too stressed. If I sense or see any kind of ongoing issue, they will be removed from the sorority setting.