The Inning Programs, as far as I can tell, replace the 'monthly task' thing where it rewards just playing lots of the game.

Firstly, you can get at least 1 star per game played which includes a 3 inning game. This seems to be more for certain scenarios such as length of game and winning, but this isn't confirmed and I can't work out exactly what is giving more stars out.

Also there is the fact you get your daily XP challenges which offer 14 a day so you potentially have 300+ stars just for doing all of them. This is a bit of a difficult stretch though but you could reasonably earn about 100 playing casually throughout the month, I reckon.