Oncr again I forgot something, did the Tsar really convert to some sort of mystic Christianity as wikipedia says?
How far exactly did Alexander liberal political views go? Was he a supporter of ending serfdom and the creation of a constitution?
Well IDK about serfdom but he started the groundwork for granting a constitution, but the reforms were sadly stopped. For instance, Alexander created the State Council, which was envisioned to be an upper house of a Parliament. For more info, read here: http://en.wikipedia.org/wiki/Government_reform_of_Alexander_I.
Yes, as I'm aware. Mysticism grew to be famously popular in Russia in the century before the Revolution.