Anecdotally, I really like the Bullet Journal system of combining todo lists with reflection. It's useful to compare the things you'd like to be doing to the things you're actually doing, and to actively contemplate the difference and changes you can make.
I’ve come across it before but never considered it that way- I too find the delta in what I’m doing vs want to be doing very important to keep in mind for achieving goals and maintaining focus, so it sounds like this might be a way to do it more effectively. Have you ever tried doing it digitally?
I mix and match a bunch of systems, some of which are digital, to create something that works for me. I think personal productivity and reflection systems have to be unique to the user. The part I personally find useful to digitize is the small annoying tasks I have to keep track of, e.g. "talk to Bob about the x, get y and z from the grocery." These tend to move around a lot and I will push them from day to day, and they don't really reflect any underlying structure or goals. At best they tell me the various sources of all the shit I have to do and could serve as indicators of things to cut out.
I prefer handwritten systems for more long-term goals, daily reflection, and projects. You get a lot more stability and emotional connection to your tasks and thoughts when you write them down in my experience. That's what I want when I'm really planning and thinking about my life. Digital doesn't seem to have the same effect. It's too easy to delete and edit yourself.
If you're really interested, this is what my system looks like. It's a mishmash of the following:
• Pile of Index Cards - I use it as the "single source of truth" for tasks and projects. I don't use the stuff about thoughts and discoveries, but I like having discrete cards I can move around and prioritize for todos.
• GTD (Getting Things Done) - I mainly use the idea that each task should have a clearly defined "next action" or a specific trigger if you're waiting on something. Ensures I'm not subconsciously avoiding a task because it has some undefined prerequisite.
• Bullet Journal - once per week, I populate pages of the days for the week ahead with tasks I expect to do from my index cards. I use that page to notice when I'm pushing tasks back and also to reflect and write down notable events from the day.
• iPhone Notes - I duplicate the task list for the day, and I move one into a "WIP" (work-in-progress) slot. This is the first thing I plan to do. It ensures I'm not trying to multi-task and do too many things at once. Over the course of the day I will peek at that list and move items around or push them back into an "Inbox," which then circles back to the Index Cards at the end of the week. New tasks go in there too. At the end of the week I re-prioritize and throw away any index cards I realize are not necessary or I no longer care about.
It sounds like a lot, but it's actually a reasonably fluid system and I'm fairly happy with it. I refine the bumpy parts when I find they aren't working.