I can't remember where I heard it laid out like this, maybe from my T or maybe somewhere else, but my order of priority for topics goes like this:

1) Any issues with my T or our relationship. If I'm upset with her (even if I'm hiding it well), the session won't be productive until I deal with that.

2) Any important present day topics, like something that's really bothering me or something I'd like her input on, problem-solving, etc. If I'm stressed, I'm probably not stable enough to want to delve into trauma work anyway.

3) Deeper themes, trauma work, childhood stuff. If the other two things are well-managed, I try to dig into the deepest, darkest recesses of my "stuff." These are my favorite sessions, but they only happen when I'm in a place to tolerate ruining my own day.

I've been re-watching Buffy lately, and it's kind of like a season of that. There is a "big bad" with a story arc that progresses through multiple episodes across the season, but there are also self-contained episodes where the main villain is mentioned only in passing or not at all.