Hi,
I've been a programmer for over a decade. I've used various planning and organization tools, from popular planners and notebooks to task managers. I noticed certain needs and built a personal planner. It's more for organizing personal activities than productivity, but it works well for that too.
I've defined these needs:
* Separate workspaces. I don't want to mix work tasks with a shopping list, cooking with a trip, or a training plan.
* Complete task manager. Bare lists cause friction, so they need descriptions, lists, projects, tags, etc. Tasks should have checklists for easier completion. They need to be easy to use.
* Notebook. But not just notes within tasks. I want them to be permanent and independent, like documentation, but optionally linked to tasks for better context
* Separate calendar. For example, if I want to plan workouts, I want a separate view and focus only on those workouts. Not everything at once.
* A journal. No progress tracking or other automated tools, which I hate. A journal where I can write down what happened, what I accomplished. Small changes add up, and a journal allows me to see them.
By the way: these four tools (to-do list, notebook, calendar, journal) work well in the "plan-do-check-act" cycle.
* One common calendar view to track all these workspaces and tasks and keep them under control.
It wasn't easy, but I managed. It works everywhere, both in the browser and on mobile devices, so you always have it at your fingertips.