I'm having a hard time, understanding where Tobirama only cared for his clan. In the manga it is written and specified towards the village not the clan.
And about him fearing Madara, i doubt it would be fear of his power. He feared more rebellious Uchiha, which would turn against the village as Madara did. He knew their hatred carried power, boosting them considerably. He acknowledged Madara's power. Because he was and is powerful. But he has no control over his hatred, which would cause harm to anyone in his path.
Your assumptions are nothing else. You state it is proven but it is far from. Because Madara had considerably power, it's not equivalent to the entire clan being stronger. They simply revealed information of how the Sharingan works. Because at the time Madara alone was stronger than most, it do not imply the entire clan is stronger. As it would vice versa imply that Senju are stronger because Hashirama is stronger than him. As far from how many people acquired partly the power which Madara had, there has only been mentioned two in that era whom awakened Mangekyou. At later time you also have Shisui, Obito, Itachi and Sasuke. Implying that Uchiha are stronger is not possible at the present time. As far as we know, they were rival clans. Which means they both were at a level of competition. Before anything more specific is reveal. All threads implying that Uchiha is stronger. Is based on assumptions alone.
The fact is the only information we received from the chapter. Is how the Sharingan works, what fuels it, and the personalities of the two Senju brother's. Everything else is assumptions. So think through it once. Before jumping to conclusion.
no offence, i like most of the uchihas but the strongest senju > strongest uchiha. deal with it and dont say uchiha > senju 
