Bear Cavalry?
I'll throw some names, without thinking too much about modifiers
Third Rome - no other Orthodox nation could've picked that one, rather unique... I am afraid it's going to be put into nation-specific decisions though, although it's a national idea if you've ever seen one in history.
Streltsy - keep, but re-think. Streltsy corps was a natural (to other nations) process of re-organizing the army, moving away from relying on feudal forces to a standing army. Discipline increase (yes, I am aware that Streltsy caused much unrest further down the road, but so did Janissaries).
Siberian Frontier - I almost started arguing against it, but then thought better of it. It makes sense that Russia gets a better a chance to colonize Siberia than, say, Spain. Russian Cossack explorers were used to colder environments. However, a bonus should only apply to Siberian and North (the very northern) American territories.
Opprichina - keep, but tie it to spy missions, reducing power of aristocracy, increase of monarch points, etc. Nothing to do with cheaper infanry, imo.
Table of Ranks - keep
Russian Idea to rule all ideas:
Science of Victory (Suvorov's Science of Victory would add shock modifiers, possibly infantry speed).
All I've got for now, not being lazy, but have a project to finish before midnight.