I think the cure for this “switching illness” happens by itself when you find yourself being very productive in a particular system/app. After bouncing between task managers a few years back, including several years on OmniFocus, I switched to Things 3 in February 2018, but Things is only partially responsible for my satisfaction.
The bigger cause was finding a workflow that works for me. I’ve never been as satisfied with my productivity in my life, and have had zero urge to switch, even when new things pop up that always tempted me in the past. This is a big deal for me because I was always the guy to try out anything new and shiny in tech. I’ve also historically been a procrastinator, and happy to be distracted by tweaking my system instead of actually getting things done.
For me Things just happened to be the tool that fit what I ended up doing. The bigger deal was my realization that GTD just didn’t fit my job, and realizing that “Next Actions” were less important to me than seeing “Past Actions,” thanks to the unpredictability of those actions in my particular situation. It’s hard to explain, but I have a zillion tasks unrelated to each other, but sometimes related to something that has gone before (but not in a way that can usually be predicted).
So I spent years trying to twist the concept of “Next Actions” to my use, and when I instead started logging “Past Actions,” something instantly clicked. Now, when I handle a task in Things, the main task field has 3 things in it - (1) the name of a case (I’m a lawyer), (2) the date I last completed a task on that case, and (3) what I did on that date. When I do something new, I have a Keyboard Maestro macro that copies and cuts the date and task info from the current task field, moves all that info to the notes field, and then moves focus back to the task field with the case name and current date. I then type what I just did, and set a new Start Date for when I next want to see it. That is when it reappears in my Today view. I sometimes but rarely also type a slight reminder about what I might need to do when that task reappears, depending on what I think might happen between now and then. But seeing what I just did, and having a log of sorts in the notes field, tells me almost instantly what I need to do next.
This has been the most freeing and excited I’ve been about this sort stuff since I first starting wrangling my tasks 25+ years ago, and I’m as excited and productive now as I was when I started it almost 2 years ago.