You can argue all you want but the fact of the matter is, Tobirama was blinded by his hatred for Madara and the Uchiha. Even after the truce he did not trust them at all. Madara could definitely see this which is why he looked at him the way he did when he interrupted him and Hashirama's conversation. Unfortunately, you can't blame everything on him due to the fact that his clan did not trust him either. If they had trusted and believed in the man who was entrusted to protect them all they might now have had to been wiped out later on in the series, but instead they chose the Senju way which led to a lot of trouble because of Tobirama and the Council.
You say Tobirama came up with democracy in the Ninja World, however it was not Tobirama alone who came to this. Pretty sure the Lords of the Fire Country had stressed it.
I do like Tobirama overall, but seems to me his hate for the Uchiha were stronger than any Uchiha's hate toward anything.