I'm no expert on this question either, but one thing is pawn structure as you said. It looks like white can make more of the d5-square than I can of d4. The next thing is about open files, I think the a-file is more useful at that stage in the game especially as it is already occupied, while bringing the rooks to the d-file would take a while.

Actually I am not sure what white should play after 8. ... Be6, everything looks pretty equal after all, maybe try 9.Bb3 Bb6 10.d4 as this seems to be the only try for an advantage. After a couple of exchanges on d4 white enjoys a small space advantage, but it doesn't look like it is enough with fewer pieces on the board.

This really is no way for white to play for a win, one has to imbalance the game earlier I believe

The position after 8. Be3 raises a question which has been staying in the back of my mind for many years.

I heard very often that leaving the Bishop on c5 would be no good in similar positions. And I always retreated it to b6 (or b3) without really knowing why.

Maybe you could explain me why it would be so bad for black to leave the bishop there. I suppose that the answer should be: look at the pawn structure!

c5 and e5 are weak and Black will not be able to stay on d4 because of c2-c3 at some point. Ok, but what would be the plan for white after say 8. ... Be6?

guioco piano sister!

Glad you like it

39.Rxd4!? even if not applicable for this game holds a very nice ideea inside (it's 1st time when I see something like this) and could be used for an endgame study problem maybe.

Nice game