I'm wondering if there is any way to make the player ONLY aim his arms while shooting, any other time the arms will just play the movement frames. The reason why I want this is because I have invisible ranged weapons, and it looks kinda odd with the arms always out front with nothing in them. I think I saw an item that had some kind of option of what the arm does, but I can't really remember or find it again....
I think what you're looking for is going to be in the spear file. It defines separate stances. Alternatively, try "arm frame override"
No problem. There is an advantage to the current implementation you have though. The stiff arm position would be perfect for a metroid mod. Combine the suit mod, stiff arm empty handed projectile, morph ball, and the super run, and you practically have a modern metroid game.