If they were lucky and avoid close meetings with dagger's blade...
What about Napoleon liberating the serfs and stablishing a French general as the Tzar of Russia? I can't really think of any other scenario outside of those two...Last time a Tsar modernized military and pushed for industrialization he got assassinated. If I was a Tsar and valued my life I would be VERY careful about reforms. 19th century Russia was basically a Christian, European Saudi Arabia. It took a guy like Stalin to finally bring Russia out of the Early Modern era.