Sorry for the late reply, but it sounds cool, after finishing the arena multiple times i do get bored, but i'd love to fight with bare hands over a barrel full of weapons.
Unfortunatly, i am not a very good modder (i haven't even made my 1st mod yet) but it would be cool if as you progress the guards or organisers like you more and allow you to enter with weapons, or maybe you could even co-ordiante a quest where they capture you and force you to fight for your freedom.