Do we need to be told how to wash in the Qur'an but not how Allah wants us to do a physical ritual prayer? What is more important?
Your question does not seem to be valid. I agree with you it is not required by Allah to teach us how to pray, you do this and do that. The method and the form of prayer is something we have to decide and agree upon . But it is perfectly fine to teach us how to be ready for a ritual prayer, since to be ready for a prayer is not part of any ritual prayer. Certainly from the Quran we can know the prophet and sahabas did some sort of ritual prayer, at the least salathul farj and salathul isha. the 5 times prayer may be a later development and this needed to be investigated. Rituals are very important, as parwez has said, it is like a police officer saluting his superior which inherently contain a message that he is ready to obey him. Without any kind of ritual a system can not continue. Do you expect a dead body to be carried and buried without following any sort of ritual? Do you expect any marriage to be conducted without any sort of ritual? Do you expect any function to be conducted without any ritual? They are very valid. When we fall in Sujood physically what is the message we convey? We are ready to obey Allah and his instructions. Where is the problem? Rituals have got its own importance and relevance whether you agree or not.