I know i’m not really answering your actual questions, but i’ll just throw TrilliumNext Notes into the mix.
It’s open source, and it can be encrypted.
If you want sync you can selfhost a server too, if not it’s local only.
There’s an android app too, but i haven’t used it.

I use a snippet manager called keep.
It runs in the terminal, and helps remember commands. I use it for remembering commands with lots of flags and parameters that i don’t use often. But it can be used to remember any command you need.
You can also add comments to each command to remind you what it does.
I add the command i need to remember with
keep new
And when i forget it i can run
keep list
To get a list of commands.
It can do more, but i’ve only ever used those two functions.

Sorry for the late response, the thunder app doesn’t give me notifications. 😅

It really depends on your usage.
/e/os feels more polished in general, but widgets are only available in a drawer when you swipe to the left from the home screen and there’s no app drawer, so everything needs to be on your home screen.
And the settings seems more convoluted and hidden, not quite apple like, but a bit less usable than stock android. Iodé has more of a stock android feel, but i’ve also encountered more bugs in it in general.

Most of my gripes with /e/os could be fixed by installing a different launcher as others in the thread have mentioned. And that would make it the best imo.

As far as banking apps and such i haven’t had any major issues. Only some government apps that require chrome to log in. So i downloaded chrome, logged in, and removed it again.
I still use google maps and it works flawlessly without login.
I don’t use any social media apps (unless you count lemmy).

Edit: aæAlso in regards to adblocking they’re on par.
I haven’t had any more ads in apps or in browser with either of them.

Edit2: The appstore on /e/os is a bit funky and i personally am not a fan.
I can’t seem to manually search for updates.
Theres google play store and regular fdroid repo and no way to add more, so you’re limited if you e.g use custom fdroid repos.
You can’t get a list of installed apps, so you have to go to settings for that.
You can’t use in app purchases (but that’s true for all degoogled appstores afaik).
You should be able to get paid apps, but you have to buy them in google play store and then log in to /e/os app store with that gmail to get it, but rumor is google might ban your mail for doing it.
On iodé it is possible to remove every app, even the preinstalled required apps like phone and files. I really miss that feature.

I have a fairphone 5 running /e/os, and my previous phone was a galaxy S9+ running IodéOS.
Unfortunately i don’t have time to write a whole review for you, but if anyone have any specific questions about either i’d be happy to answer them when i get time.