There seems to be a bug with the leader stat. According to the tooltip, it is supposed to increase player effectiveness but it seems to do the opposite. I get way more homeruns per game with the manager with 1 in leader.
Also, late game it seems that the only thing that matters for income is hitting homeruns. A strikeout earns around 200k, a triple 4m and a homerun 21b. Admissions is around 1b/game. This makes it way, way too slow to earn enough to buy the later upgrades which cost 1qu.
Otherwise, it's a good game and I enjoyed playing it.