It's not too difficult to imagine that, in a world without what we call World War I, there would have been considerable upheavals in the more authoritarian regimes nonetheless:
- After Franz Joseph dies and is succeeded by Karl, Austria-Hungary liberalizes and federalizes: Hungary may not like it one bit, but going it alone as a landlocked nation is none too attractive either.
- Hemophiliacs don't live long by the very nature of their genetic disorder. It's not hard to imagine that a simple household accident could prove fatal for the Tsarevitch. In turn that could discredit Rasputin completely, and bring the ruling family into total disgrace for allowing Rasputin into the inner circle. That could lead to the Romanov's exile, with a collateral branch getting installed as a figurehead tsar in a parliamentary nation with, say, Kerensky at the helm. At the same time, subject nations (Poland; Lithuania; Latvia; Estonia; Finland; Ukraine) could easily break away.
- Germans would see the liberalizing moves in Russia and Austria-Hungary and reason, "Why not us?", leading to a quasi-revolution in which the Kaiser is forced to choose between submitting to a constitution (and thus becoming a figurehead) or complete ouster.