I am very fearful of posting suggestions to more experienced people for obvious reasons - but you did ask,

Biggest gain that I can see, would come from cutting down the time between fights (more fights, more action, crowds+teams happier etc)

Best ways of doing this and not compromising safety are -
Cut down load+unload time : new door ? 2 doors ?

Cut down arena repair time : Better floor surface ? Ban Mute ?

Only random thoughts.
Roger