Ok... Like the length and thickness of the body. Nice top line. Dorsal is tall and has good volume.. but the first rays are stubby. Many bettas have the same fault.. as a breeder you work to making that longer.
Tail is short. Look at the length of a dorsal or even an anal ray and you can see the tail rays are shorter. You get that when you breed for branching sometimes. As a breeder you must watch both.. length and branching. So if you breed this male look for nice branching on the girl but also length. And watch future generations. He is not quite 180 here though he is close and may get there fully flared.
Anal is a tad long. It is longer than the dorsal and next to the shorter tail it does affect the balance of the fish. but it is level.. so workable.
Color.. he has a BF pattern but it is not clean. Good contrast between colors but the red bleeds down into the white. You may get some marbles, solids as well as the BF pattern in offspring.. and if you get BF's, the ones with a nice dividing line will be the better ones to show and breed.