I can't really change the tempo, because in the game, the music is mixed with the battle music when you get near an enemy. I have a battle song for 70bpm, 80bpm, 90 bpm, 100 bpm etc, so I can't have songs with a tempo in between those.
Thanks for the comments, and you're right, I still need to add fx.
Thanks for the comments, and you're right, I still need to add fx.