So I decided the list should be done before lunch, which meant I could pick anything on the list, but it had to be something on the list. And after lunch, I have a list of three big-picture projects I can work on. I can choose any one of them, but it has to be one of them. Their next steps are reasonably well laid out, because I don't think I do generally have executive dysfunction issues, so I get to pick one of three projects and work on it until dinner.
This has saved my sanity. I don't waste very much time at all now. I don't do well with strict routines, but these buckets take so much of the guess work out. In the morning, 15 options. In the afternoon, only 3. It's so much more manageable.