My PKM journey

I've tried a LOT of Personal Knowledge Management software in the journey for the perfect way to record all knowledge I want to save.

TL;DR: I've tried a bunch of apps to try and replace a combination of Todoist and Obsidian. What software and system do you use to keep track of personal knowledge and tasks?

What I'm looking for
There are three different attributes I am looking for in a PKM, in the following order:

1. Ease of use. I need whatever I use to be really easy and frictionless to record information with. If there's too much resistance to getting information into the application than I probably won't end up saving it and I'll just forget about it.
2. It needs to be easy to surface relevant information but also browse through less relevant information. This one is sort of a few sub categories. On one hand, I need reminders, due dates, and the UX to make sure that I don't miss certain tasks. On the other hand I need to be able to categorize and view all recorded entities - tasks, as well as pieces of information unrelated to tasks. This means I want to be able to categorize the information in a way that allows me to filter down from a larger list or from completed tasks - the best way to do this is usually tags.
3. I like to use software that doesn't allow the developers to access my information; usually this is done through end to end encryption. This is especially important in a PKM because of the volume and sensitivity of the information being recorded. However, this is last on the list because I use multiple devices which introduces additional surface vectors if someone were to try and get my information. End to end encryption is just a nice to have.
4. A bonus, being able to share tasks in a secure and easy way with my significant other.

Where I've been
Todoist
I won't make you read the whole post to find out my favorite... it's Todoist. I've used it for years! It really locks down that first attribute, ease of storing tasks. Todoist makes it really easy to add tasks, move tasks, and reschedule tasks. It's a simple and functional task manager that really works for me. I basically use it to keep track of everything across several projects. I roll over most of the tasks from day to day until I'm able to complete them. For tasks that need a reminder I add a due date - the reminder system is pretty basic but it works. It's the app I keep coming back to after trying all the others. But being primarily a task manager it lacks the ability to store information not related to tasks. Like information about people, places or things. So I searched for another app.

Obsidian
I'm trying this out on Obsidian right now! It's a wonderful piece of software that has full end to end encryption. I use it as a sort of digital "safe" for information I definitely don't want to lose. Unfortunately Obsidian lacks some critical functionality:

• Tasks are just checkboxes. There are plugins that can help you handle them better but the native UX for managing them is just copy, paste, and delete.
• There's tagging and folders but there's no real way to move through lots of semi-related pieces of information. I like a big list of stuff that can be filtered down, not lots of scattered documents. All of the linking and tagging happens in the middle of the rest of the text and a list of backlinks at the bottom of the UI.
• Maybe this sounds silly to you the reader - but basically it's all just too manual. If Obsidian had a sort of "parent note" at the top of each folder - like Notion which I'll cover next - it would make Obsidian a lot easier to use. Instead I always have to choose between a new block in a note, a whole new note or a folder. I'd love to be able to write out stuff as I think of it and then move stuff into sub folders - or lists - more easily.
• It's expensive for a journaling app with a relatively basic feature set. Note to note linking and cloud sync are just expected features at this point for an application like this.

Between Todoist and Obsidian I am able to meet all of those listed attributes:

1. Todoist makes it easy to enter information and make sure I remember it when I need to. I can write a reminder in Todoist to make sure I record information in Obsidian.
2. It's pretty easy to keep track of a lot of relevant tasks and other pieces of information in Todoist. For information that I need longer term or isn't related to a current task, it goes in Obsidian
3. Obsidian is end to end encrypted. Anything related to sensitive stuff goes in Obsidian.
4. Todoist allows setting sharing at a project level. So this makes it pretty easy to share tasks.

After using this system for awhile I started to see cracks forming. Todoist makes it easy to keep track of tasks but complex projects are often hard to manage. It's easy to lose track of tasks that are further out then a few days without using obtuse filters. Obsidian is difficult to use on mobile and having to transfer information from Todoist to Obsidian is frustrating. There are probably Obsidian plugins I could use to manage some of this but then I'd have to evaluate each one for data privacy concerns. And paying so much for Obsidian it's a little frustrating to have to rely on community plugins.
So I began looking for a new application, one that could do it all.

Notion
I still use Notion for a few different very specific things. I could probably use Obsidian or some of the other apps I'm about to talk about for these things. But I really like Notion - when it first came out it blew me away! It did so much stuff! It's great for keeping lists of well categorized pieces of information. It has great support for tagging, and the aforementioned folder / page hybrid. It's basically a wiki software combined with a task manager. A few issues keep me from using it as my main application:

• Like Obsidian it's hard to use on mobile. Especially for complicated stuff like moving through lots of different pieces of unrelated information.
• The reminder system is clunky. Since everything in Notion is a "block", reminders are tied to them. I think if I put a lot of time and effort into building a process for keeping track of my tasks it could work. But again, I don't really want to spend that much effort when I have system that already mostly works.
• There's no end to end encryption and nothing but a true / false value assigned to your user keeps employees from accessing your information easily.

A great piece of software but ultimately one I moved away from after a bit and back to Todoist.

Workflowy
This was the first time I felt a real paradigm shift. Workflowy is basically a really big list. Every bullet on the list is a "node" and you can zoom into nodes endlessly. So you can go from seeing all of your information to seeing very specific pieces of information very quickly and easily, even on mobile. And entering information is a breeze, you just add it as a bullet and then move it to where you need it. It's amazing for what I like to do, which is start with a general idea and build more and more specific information. For example, when going on trips I could create a "trip to place" bullet. Workflowy has amazing support for two way linking lists - basically you can change a list in one place and have it updated in all the other places its linked. So I could have a packing list that I link to the trip to place bullet. Or I can copy it and add to it. You can see all the possibilities and the UX makes it seamless.

The real killer here for me was the lack of reminders. The way to handle due dates in Workflowy is to literally type the date; there are UX solutions like a pop out calendar that handles this for you. And then you can filter down to bullets that contain that date. In theory it works well but it requires me to make sure I am looking at the right information when I need to be instead of the other way around. I tried using Todoist to supplement this but ended up having to constantly check both to make sure each was properly updated. If Worflowy had a way to assign reminders to bullets so a notification popped up that would make this the perfect app. In fact, I might give it another try after writing this out!

Lastly, it doesn't offer end to end encryption.

Twos App
This is the other app that got really close to being perfect. Twos App is the software that touched the sun and lost its wings. It does everything! It's sort of similar to Workflowy where you can have checkboxes (tasks) and bullets (pieces of information). You also have lists. So you can start a "shopping list" that sits outside your daily tasks, and you can fill that list with items you need. Then when you are ready to go shopping you can move that shopping list into a "day" and it's automatically a task. It also has a pretty good reminder system.
The problem with Twos App is unfortunate: the bugs. I found it doing odd things like reordering items, separating them out of lists and just generally glitching out. My theory is that the app is so feature packed that the systems start to conflict with each other. I've seen they are going to release a new major version soon so I might give it another try.

This is getting way too long! Just real quick some others I've tried:

• Capacities. A lot of protentional, like a more structured version of Notion. It shares a ton of the same features and functions similarly. But everything revolves around "objects" which are basically just... templates. There's no inheritance or ways to compose objects that would make something like that really powerful
• Amplenote: Another app that is close in theory but one big thing is it lacks the ability to tag tasks. You can only tag notes, which tasks live inside of. There are UX solutions for this but it's pretty clunky. It also supports end to end encryption but on a note by note basis? It seems like another situation where if I put a lot of time in I might be able to get something working but just doesn't seem worth it.
• Loqseq: End to end encrypted! Great support for tasks! But I think it's just still too underbaked. The sync feature is still in beta and requires you to pay in the form of donations? They basically tie your account to the donations you make and then give you access. Seems not worth it for the current set of functionality. It also lacks task level tags, like Amplenote.
• I've also tried Day One, Daycast, Standard Notes, Legend, and probably a bunch of others I'm not listing. I almost forgot about Ticktick.

So this brings me to my question: what application and system do you use?