Clunky baserunning kills way too many innings. I find the opposing team turns into fielding all-stars way too often. But, the #1 issue I have is the balls/strikes calls. Even when clearly more than half the ball is inside the strike zone box, gets called a ball... for me... exact same ball position for game controlled team is usually a strike.
Just too many instances of all the above to make it enjoyable. Becomes frustrating instead.