Ninja is my 60 tank community male Betta who has lived peacefully since January with the resident 10 Tiger Barbs 2 silver Dollars, 3male molly's, 5 Tetra Minors, 3 Cory, 1 Dwarf Gourami, 3 otto's and 1 Gobi Dragon.
So I bought a new male Betta for my 120 tanks thinking he would certainly get along with my resident 4 angle fish, 6 BP's, 1 Pleco, 4 Otto, 3 Cory, and 3 female molly's. I named him Assassin because during the day he was placid, friendly and peaceful, but I discovered that when the evening lights were turned off he was attacking my largest angels tenaciously. One angle particular had gill wounds with gill wounds I discovered the next morning. Thinking that perhaps swapping him out with Ninja in the 60 tank would be more compatible with faster swimming fish as angles are slow with flowing fins.
Everything seemed to work out fine with Ninja being his calm peaceful self with the angles in the 60 tank and Assassin looking much more calm with the with the more confident Barbs. Then it was lunch time and Assassin's true colors came out by not allowing any community fish to get near the food with very threatening posturing. So Assassin now had his own large floating breeder tank and seems content while Ninja still remains a peaceful member of the community. So it appears that not all Betta's can live peacefully in community tanks regardless of the compatibility match up.

Ninja remains at peace in community tank.