This will be the best idea ever. Having huge outside arena screens would allow all the heroe's to remain outside while the combantants fight it out at the same time re-ducing the lag of hundreds of people sitting in the arena, whic I assume would be another area that can be affected by load time of numerous heroes. You could even place numerous TV screens throughout the cities.
Oh what about Blimps that fly through the sky brodacasting the next arena fights

that would be cool. I predict major lag issues when this comes out

. We need to battle evil lag issues.