Thank you for your nice comment !
I didn't think it was possible to hold Königsberg against the initial Russian onslaught. Impressive. After the AI kicked me out twice, I never tried that again.
Actually, given there is always the same number of Russians attacking, you can pretty much reproduce it. The key is to put the good person in charge, i.e. little bro, the only available Prussian leader with the Master of Defense strait, and good stats all around. Also add as much fixed guns as you can - they are really critical.
It seems Baris survived his winter retreat after the Königsberg defeat relatively unscathed. How did he do that? And why didn't he try again the next year?
Actually, he did not. I believe he had huge losses. In any case, I believe if he had seriously attacked me the following year, he could have kicked me out. He did not, even though he had nothing better to do with the Russian (he probably minded the NM).
It's strange how most AAR writers like to take gambles and tend to be overactive. We all seem to ignore the golden rule of AGE games: play it like McClellan and you win, play like Hood and you get crushed. In other words: when it's doubtful whether a move will get you an advantage, don't move (and win cohesion and entrenchment). At least that is what I used to think, your AAR is starting to convince me that playing the Prussians restless activity might be the better strategy.
As the Prussian against a player who is going to be systematic in his attacks, you have to be mobile, if only to shift troops from one front to the other.
After the failure to take Prag, I knew I would not win without taking risk. I came very, very close to disaster at the very end of 1759. My whole army could have been cut from its supply sources, and anniliated.
Please don't take this the wrong way, but I really had a hard laugh when I came to the part where you lost three of your army commanders within two turns. That was so much bad luck, it was almost a tragic comedy. Seems it really is a bad idea to leave the HQ stack depleted. Learned yet another thing.
That was an horrible surprise for me. I am never going to put commander on their own now. I ll use the "Garde du Corps".
I like your strategy in 1758: Concentrate your forces against one foe and trade space for time everywhere else. It paid off beautifully for you in Saxony.
It gets better

But if I had to make a wager, I would still bet on Baris. Interior lines and better commanders can't beat numbers indefinitively.
Well, if you read until the end of the AAR as written for now, Baris does not have the "number" for him any more.