Listen to you all not just because you can breath fire like some mythical dragon means you have the upper hand, we all remeber the nature element circle, suikon is stronger than katon.The senju hashi was powerful compared to madara
1. Water (suikon) vs Fire ( katon) in the element circle
Even if madara had some how mastered fire to its peak it would be lame or weaker to some one who had mastered water to its peak.Remeber the wooden style shodai had mastered both doton and suikon to the extent of forming a new element mokuton. so in term of fire to water. the shodai had the upper hand
2. The First's ability to control the bijuu
Remember kishi's writing...this dude could control the tailed beast has his own, to the extent of giving other nations. So even if madara somehow sharinganed the bijuu it would still be controlled by the senju..and he had mokuton which has effects to bijuu.he can bind them with his wood style while doing some spanking to madara..
3.The first's chakra ability and byakougou
The firsts chakra was said to be in motion,movement all the time, this is against genjutsu type users.Even if you cast a genjutsu on him it would be distorted /cancelled. the dude could heal is wounds without twitching fingers and mumbling poultry.
4.He was close to the uzumaki (the clan was known for its sealing abilities)
Dont look at mokuton as just water and earth...why would they need the firsts cells to do mokuton...its mokuton is life..living things you have to know ying and yang..you have to breath life to your trees..
If it came to me madaras only option to fight the first was taijutsu..all madaras ability cant work on the first..
lastly he had the scroll of sealing when it came to taijutsu..and the very first technique was kage bunshin..which naruto until now uses it to defeat the likes of pain and kiba's..
in comparison to the first narutos bunshin is no match for the shodai.
just a thought could tobi be senju hashirama? hehehe