Danger Bird
gravity's angel
That's why I build the Forbidden Palace, to counter maintenance costs. And when I'm in central Siberia I will quickly build a Summer Palace.
Later in the game I will adopt State Property. Actually, I will aim my research on that.
But it's all about balance. I build settlers, mostly in Moskva, but also markets, courthouses, banks, etc.
For all the new cities in Siberia I have the same building que: walls, castle, theatre, forge, courthouse. That's what any city MUST have before building anything else.
This game I'm very advanced, because I restrained myself in expansion.
Most earlier games with Russia I managed to settle 7 cities in Siberia BEFORE 1700 AD. At that time I didn't even had banking yet.
I am watching this with interest, because I've also tried creating Russia to the full extent (to Vladisvostok and Kamchatka, at least) a few times, and your game is using a very different strategy to what I have done. I'm anxious to see how it works.
I usually have only five cities west of Urals when I build my 7 Siberian ones. So I'm also worried you are going to kill your economy/research, as I said before. But, I'll see how it goes for you.
Also, are you sure you want to invest time and hammers into walls/castles in Siberia? Best, I think, to never let the Keshiks near your cities, using roads and pikemen. I usually start Siberian cities with granary > courthouse, but I guess that's because I am ultra-paranoid about stability.