Ur theory was gr8 but dere were some loopholes
1. Madara was d one dat killd his brother because he was already blind due to his overuse of d m.s nd after he transplantd his brodas m.s to enable him not to be blind and more importantly to be able to fight and protect d uchiha so d main reason madara is ANGRY at d prospect of peace is dat he feels his brother died 4 nothing
2. Hashirama inxtigating a death match...itx highly unlikely cuz kishi hax gone xo far in making hashirama d best shinobi in d world,dnt tink kishi wuld want 2 troll ux dat hard
3. Tobirama actually xpending time tinking inxtead of being d brawn that he is well no one knws wat plot twist kishi's gonna make
sorry 4 making it 2 long but still rep for ur theories