Looking at both current and historical data combined @ juckins. com.
The chance of missing your connection in Sacramento is between 0% and 3.3%.
The chance of missing your connection in Galesburg is between 1.6% and 6.7%.
The chance of missing your connection in Los Angeles is between 20% and 34%.
The chance you are going to miss your connection in Sacramento or Galesburg is small, but possible.
The chance you will miss your connection in Los Angeles is higher, but the most manageable - If you miss your connection, they will probably put you on a bus to Bakersfield, and then a San Joaquins train to Martinez, where you will meet the Coast Starlight that you missed in LA.
Just keep the possibility in your head that you MIGHT have to spend a night in a city you are connecting in. Amtrak runs the train every day on the routes you plan to take and they will almost certainly compensate you for your tardiness if you miss your connection.
Delays happen and they can be large, so you should keep it in your mind on the backbunner, but it isn’t something to actively think about. I’ve had trains cancelled, connections missed. Things usually have a way of working out.