Oh, some lucky Betta will be getting a wonderful home. You're right, the danios are out. 2.5g is the minimum for a lone betta. Besides, most like it like that. This way they command your attention. lol
There are several types of Bettas some are supposed to look the way you describe.
I'm not up up the identifying them. Some where in the forum archives is a thread with links to the different type. If you do a google search, you'll find them.
Younger Bettas are small, maybe an inch in the stores and their fins aren't as well developed as older Bettas.
Frayed fins will heal in a warm cycled tank with some extra stress coat and couple of drops of garlic juice to help their immune system.
Have fun Betta shopping. The perfect betta will find you.
