Akira is Japanese for bright. Maybe that'd work?
Hey, cool. I just got a white wakin with red finnage and named him Akira. I liked the bright white meaning, plus it's for Akira Kurosawa (filmmaker).
Most of my bettas have always been named Henry Limpet. (I know, I'm weird. And I'm okay with that.)
I have two bettas now and this time I went with favorite singers -- so their names are Eros and Janne. (For Eros Ramazzotti and Janne Tulkki.) Andrea Bocelli will just have to wait his turn. I'm sure he can cope.
If you like the fire, blaze, inferno ideas... you can run those words or some others through a foreign language translator. I come up with nice, unique names that way sometimes. Name him after people you liked a lot or admire from your past.. historic figures.. TV or movie characters.. science fiction writers.. songwriters. I had a neighbor once with big dogs inclined to be fighters. He'd named them Lance and Pierce.. a little too graphic, I thought.. but okay.
So far.. of the suggestions made, I like Blaze the best.