Maybe instead of having each file to each coordinate saved, it stored as a world name / server IP address. For example the world name is Test then, the text file would be Test.txt, Then, inside of it is

---------------
<the name>
X : <x> Y : <y> Z : <z>
---------------

And go on, so each time we saved coordinate in the same world, the file get bigger for example

---------------
House
X : 100 Y : 70 Z : 100
---------------
Spawn
X : 0Y : 60 Z : 0
---------------

Then maybe there is a setting (which accessible by using modmenu / hotkey)
We can set two different option
1.

---------------
<the name>
X : <x> Y : <y> Z : <z>
---------------

---------------
<the name>
X : <x>
Y : <y>
Z : <z>
---------------

And then, maybe add like the - length? (ik its kinda stupid but its okay)
so there is a slider to adjust the - length
Also the last thing is there is an option to instead of storing them as server IP, it stored as the name

Ok, that is all of my suggestion

These are good ideas, I will look into them when I get the chance. I like the idea of per-world/server coordinates. I have never done any config style screens with mod menu but that does seem like a good idea.

Also, maybe add copy coordinate button? for example to send the coordinate to friend, etc.

Oh also, i forgot something. Dimension! so
1.

---------------
<the name>
Dimension : <dimension>
X : <x> Y : <y> Z : <z>
---------------

---------------
<the name>
Dimension : <dimension>
X : <x>
Y : <y>
Z : <z>
---------------

For example

---------------
Nether Portal
Dimension : minecraf:the_nether
X : 100 Y : 50 Z : 100
---------------

(the dimension also use the namespace, so it can support modded dimension?)