Also realize that a sorority group is just that - often related females from spawns raised together
If you toss group of unrelated females in a tank, be prepared for the winner takes all possibility - make sure there is space enough & lots of plants etc to break lines of sight & floating upper level hideaways as well as lower escapes
Often seriously overcrowded female groups in shops will appear to get along, take home 5-8 & they will sort out the hierarchy ... it's best to be prepared to jar females as needed
It's not the sort of photo of your male where his conformation, scaling, colour, fins etc can be assessed
I assume Ct is multi locus like most tail forms, what are the extremes you need to watch for? should one parent always be heterozygous?
There are some very good Betta sites & forums
If you've not been, definitely go to a Betta show
Bettysplendens is one of my favourites - great genetics summary with photos for colour & finnage
Holland Betta Show has a great site with past winners etc gallery which is great for learning conformation etc