Mine has to be “The Arena Stage Ver.”. It’s freakin’ badass!
“New Days” is a relaxing song.
Heartfelt cry. I train to it, I fight to it!
Yo, we all know “Reach Out To The Truth” is THE ONE TRUE SONG
Battle for Everyone’s Souls.
“New Days.” My other favorites are Princess Amagi, Like The Dragon, Missions of the Brilliant Executioner, I’ll Face Myself, and Electronica in the Velvet Room.
Probably Battle Hymn of the Soul, but it’s a tough choice because I love Persona music. So many good songs made it in the game, even if they weren’t all battle themes. Basically any song from Persona 3 and 4 I’m a big fan of. 
Teddie Circus
Personally I love The Hero from Junes
Now I face out
I hold out
I reach out to the truth of my life
Seeking to seize on the whole moment, yeah
I can really get behind “The Wandering Wolf”.
Also the music from the Instant Kills, I think it’s called “Mist”
The Almighty & Heartful Cry
I love Persona 3: Unavoidable Battle, and am a bit sad it’s not available as a stage track in P4A - but it pops up in story mode so it’s cool.
It’s such a simple guitar riff, but it’s sends sheer waves of awesome up my spinal chord, so that’s why I like it.
Mass Destruction is hype as fuck.