I'd rather just have no kingdoms in the Russian area since if you start at the Stamford Bridge start, (like most people) the grand principality of Rostov always seems to form Rus since it has just enough provinces to form a kingdom. This one feature ruins playing as the Russians. Maybe have a very large kingdom of Rus that encompasses all of kievan Rus, so that it actually requires some skill other than saving up a lot of money and piety to form Rus.
I know we've moved past this point, but I took a look at this duchy when testing out the new DLC, and discovered that they have 16/29 provinces of the Kingdom of Rus', 55% of its territory. If you were to add 4 or more provinces to the Kingdom of Rus', though, they would no longer have enough to form the Kingdom of Rus' immediately. Now, the devs probably don't want to add 4 new provinces in the area, so this requires moving four provinces from another kingdom into Rus'. I've looked at 4 possibilities:
Possibility 1: Move the Duchy of Ryazan' (4 provinces) out of Ruthenia and into Rus'. This move has the advantage of making the most sense from a historical standpoint, but unfortunately, removing 4 provinces from Ruthenia means that the Grand Principality of Galich has enough territory to form the Kingdom of Ruthenia at the beginning (11/21 instead of 11/25). Essentially, it just moves the problem further south.
Possibility 2: Move the Duchy of Hlynov (5 provinces) out of Perm' and into Rus'. This move makes the borders of Rus' and Perm' look a little bit better. Sadly, this one also moves the problem. In this case, the Duchy of Perm' has enough provinces to immediately form the Kingdom of Perm' (5/10 instead of 5/15). This might actually be a good thing by upping the prestige of one of the pagan kingdoms, but I regard it as once again moving the problem instead of fixing it.
Possibility 3: Remove the province of Zyriane from the Duchy of Hlynov to the Duchy of Perm', then move the reduced size Duchy of Hlynov from the Kingdom of Perm' to Rus'. This solution eliminates the problem completely, as it means neither the High Chief of Perm' nor the Grand Prince of Rostov can immediately declare themselves kings and strut around Russia. This does shift things in the pagan areas, though, which may be problematic. Another downside here is that the Duchy of Hlynov ends up being a long chain of provinces, which looks weird, but Franconia is already like that and if it's good enough for one of the core duchies of the HRE, it's good enough for the very edge of the map.
Possibility 4: Move the Duchy of Karelia (5 provinces) from the Kingdom of Finland to Rus'. This would solve the balance problem in Rus', and parts of Karelia were taken by Novgorod in the time period, but still, at the beginning of the time period, any Finnish kingdom would almost certainly include or wish to include Karelia.
So what do people think about these ideas?