In your request for advice, you ask what part of Pure Baseball is related to "defense".

Defense is important, as is pointed out in earlier posts to your questions. The issue as I see it is how much a percentage of the total PB game does defense play. I assume that defense is roughly 10% of the game. I also assume that pitching is 40% of the game and that hitting is the rest, 50%. These assumptions are subject to debate and criticism; but you need an analytical framework to approach the game.

Just remember this; a good defense can improve your pitching so that it can surpass the 40% assumption. This will not reduce the hitting portion. What happens is like grade inflation in the high schools. 100% becomes 110-120%. That's Ok, but hard to measure. In PB, defense is an elusive but important factor. Good defense shows up in the last few innings of important, well - pitched games, just like in real baseball.

In your questions, you assume that rotisserie baseball is not applicable to PB team analysis. It is a good assumption with regard to position players. Stolen bases and RBIs play way too much importance in roto ball.

Roto pitching categories are much more useful to picking pitchers in PB. Forget saves and wins (any pitcher can be a closer in PB, not in Roto). Other Roto categories are very useful in evaluating pitchers in PB, particularly whip & strikeouts,

Throw in Park factors, righty-lefty factors, and PB becomes a sophisticated game requiring expert analysis. Good luck.