Excellent observation. The timurids would not be so threatening if most factions have jinettes. I think only the Polish/Hungarian and Spanish/Portugese have javelin throwing cavalry. Someone correct me if I am mistaken.
Russians have it too.
They have Boyar's sons. Well armoured (they are somewhere between heavy and light cav. Fast as light more armoured than light, but lack a bit of armour.) and armed javlin throwing calivary who when out of javlins can whoop out their axes and start choping anything with armour with their AP axes.