One thing I have noticed in my own GTD system is that the choice of next action is important. Some next actions really do bring me closer to a project outcome, but others don't don't seem to move me closer at all. The insidious thing about the second group is that they sound like they are the right thing to do.
For example, I need a new extension cable for my office. I have already measured the required length and counted the number of plug sockets, so the next action is "Google for comparison reviews of extension cable brands". Sounds great, except that none of the reviews of extension cables are useful to me. They tend to compare things like the features of the cables rather than more difficult to discern things like fire risk safety and expected lifespan. A much better next action for me would have been "Make a shortlist of extension cables". After that, I would have a list of several that met my requirements, allowing me to ultimately choose and buy one of those.
I feel that in your case, buying more GTD gear might not move you closer to the goal of a working GTD system that serves you. Practising the core habits will move you closer to that goal, and since you mentioned not having done the weekly review in a month, I suggest that the next thing to do would be a weekly review. Don't worry about getting it perfect. Just do one. Afterwards, you can reflect on how it went and what yo can do better next time.
I do, however, understand the allure of gear and accept that you are more likely to pick up and use gear that is attractive to you. I use Moleskinne notebooks and a mechanical pencil for my lists, colourful folders and a label maker for my paper files, and Obsidian for my digital notes. Given that you are thinking about digital tools, I don't think my choices will work for you.
