I've recently migrated to using Obsidian as my software (in fact, I use Obsidian for everything! [...]
I use #Obsidian as well--taking notes on a variety of things such as projects, ideas, problems, interests, reminders, etc.
I've tried some different note-taking methods but those work for some aspects, but not all aspects of what I need to remember.
I agree, different things will require different solutions. There isn't a perfect method for note-taking, otherwise everyone would probably be using it by now. To further highlight this issue, I believe looking at the considerable number of plugins and note-taking apps illustrates this. Regarding some things, I'm still trying to figure out what works for me. I doubt I'll ever find a perfect solution either, but I'm okay with that because perfection is overrated IMO.
The way I use Obsidian is by having the daily note set up with a template which is timestamped and asks loaded questions, with tags, to help me find what subject I want to look back on in certain dates.
I do something similar, but I've revised how I approach my notes. In its current form, my daily notes are only filled with pages for the notes I make that day. I use tags very sparingly, only to highlight key ideas. In the first iteration of my vault, I realized that I had a tendency to overpopulate my notes with unnecessary tags. Currently, I use a hierarchical system to label my notes. While this works for me, this may not work for you, and that's okay. It's just something I've become accustomed to after switching from #Windows to #Linux. Organizing my notes in this manner allows me to navigate through my notes more quickly and effectively than rummaging through a folder-based/GUI-based methodology. Utilizing header markdown was also useful for dividing some pages into different sections which could be referenced by various other pages.
So I have tried writing EVERYTHING down.
[...]These tags can be relating to work, emotions, relationships, interactions, and ways to improve any of those.
I respect the hustle, but the mental overhead for this project sounds a bit excessive. It seems unrealistic to remember and process the information as you're doing. This obsession with does certainly sound like ADHD, and I'm speaking from personal experience. I've embarked on something similar, but realized how time consuming a project like this would be. However, if this truly is important to you, don't let me stop you. My own vault of notes is very important to me as well.