The question is in the title. What if Timur also known as Timur-i-Lang or Tamerlane never became the brutal conqueror he was in OTL. His wake on Asia fundamentally changed Eurasian and all of World history. He was infamous for his brutality and known for his patronage of Persian and Islamic culture. His claimed the mantle of Genghis Khan as a Turko-Mongol. I would assume that the Ottoman Empire would fare much better, the Tughlaq dynasty of the Delhi Sultanate would fare much better, and that many Genghisid states would last much longer. Most of all, 5% of the world population would not be killed. But what major cultural, social, economic, and cultural differences do you see in this potential TL in the long term?