Vim has made a stupid design decision, and we're still eating shit many years later.

It prioritised mnemonics, rather than ergonomics.

The issue is pretty apparent: mnemonics are helpful for the first, like, week while you're learning vim for the first time.
And then many years later you still end up using the same non-optimal mappings.

One of the most frequent things you do in a text editor, is copy.
And yet it's mapped to one of the most annoying keys to press: y. While powered by a big stretch of a mnemonic that we just came to accept: "yank".

And yet s sits there undisturbed, in one of the most prime finger positions on the home row, doing what cl can also do.

Don't get me wrong: I loved using s, but it is too convenient of a placement.

I hate pressing p almost as much as pressing y.
It is another example of an 😩 key used for one of the most common actions. Except, pasting is probably more common than copying.

o is one of the nicest to press keys, yet it's there for a fairly niche action: creating a new line.

What I find myself doing the most after creating a new line, is to create another line.
Because o puts you into insert mode, the natural way to create another line is by pressing enter.
Yet, the hand motion of switching from o to Enter is pretty cumbersome.

What is the most common usecase for A?
In my experience, it's to add in a ; or a ,.
However, if you correctly use both shifts, the hand movement to do an action like this is a bit too ridiculous: for such a common usecase, having to move your pinky aaaaallllll the way from the right shift to ; ends up compiling into an annoyance.

The choice of a is also strange in a different way.
To insert at the left of the cursor, you press the right key (i). To insert at the right of the cursor, you press the left key (a).
???

you can stop eating shit

Defaults are made to be CHANGED from.
It's great when they are good to begin with, but that's not always the case.
Do not be afraid of change when it can provide you a much nicer experience.

My copy key is now s.
What's the mnemonic? "Steal"?
Wrong question. I don't need a mnemonic! If the mapping feels right, your muscle memory adjusts pretty quick!

Now I don't have to travel across the Alps just to copy something: the key is on my home row.

My paste key is o.
Much nicer to press than p! And in addition, something like yyp is now sso, which I find to simply be much more enjoyable.

Insert new line is now on a.
Now when I insert a new line, the motion of my right hand to reach Enter is much smoother!
Smoother even if I do "insert new line above" (A) first; all I need to do is slightly move the right pinky from right shift to Enter.

Insert after the cursor is on p.
This was risky in my head, because I don't like pressing p. But very quickly I realized just how much nicer it is than a for the purpose.

First of all, it is on the right side of i! So, i and p now play along with a consistent semantic of "this one is on the left, this means before" and "this one is on the right, this means after".

But even better than that, appending is AMAZING now!
The hand movement to append a ; or , at the end of the line is way smaller now, and feels really comfortable.
Also generally, pressing right shift is more difficult than pressing left shift anyway; so overall there's less hand movement for something that I do really frequently, especially while writing a blog post for example.

After changing these, it took me maybe two days to get used to the new mappings. This is simply because of how much more fitting they feel in my head, and to my fingers.

You will have your own gripes that you will solve differently than me, but I wanted to shed light on that it can be really beneficial to change defaults, even when they are as strong-rooted as the ones I listed.

It's true: a lot of other programs will replicate vim, and have semantically fitting hjkl, y, p, etc mappings.
What do you do about that?

Personally, I just context switch, or reconfigure the mappings. This may seem like a lot of effort, or a non-ideal solution, but look at it from a different lens: why would you sacrifice your experience in the place where you spend most of your time (your editor), just for some other program to feel consistent?

I do agree, context switching is annoying, but can be learned: if you have a strong thought of "this is a different program", you can eventually stop caring that its mappings are inconsistent with what you remapped. Or, you know, remap them in that program as well.