Hi Chris, As I understand it, you know the likelihood of actually *missing* the northbound Starlight is very low, it's more a case of it's being late to Sac'to, to the point where you won't want to sit up and wait for it. Yes, that can happen, but usually won't. Some people stay on the westbound CZ to Martinez, and change there, so they can get on the Starlight a little earlier - but that's not one of those guaranteed connections like Sac'to. You could, as a separate issue, book the round trip from SAC to MTZ - people do it, and then just cancel if you can see that it's either not going to work (CZ is late) or not be necessary (Starlight running on-time). You can use
https://asm.transitdocs.com/ to keep track of train status as you travel.
But I've done that transfer once, and I just gritted my teeth and waited up for the Starlight. There isn't much to do in that neighborhood after about 9pm. I dragged out my dinner in Old Town Sac'to about as long as I decently could, then went back to the station to wait. You should be prepared to be entertained by people watching - you'll have plenty of company in the station. We had some excitement because a waiting passenger had a medical event, not too serious, but enough to call a team to take him in for observation. Our Starlight was a little late (like 30 minutes, or so), which made falling into bed in my roomette all that much sweeter.
For your entertainment, here's the last month of northbound departures for train #14 in SAC. It seems to have deteriorated since I made this connection. Consider your options - and good luck!