[asimovDev]

I have had similar thoughts recently when attending language courses where I write a lot of notes by hand. This problem is exacerbated by umlauts. If the language doesn't have letters like ō (are there any? i only see this letter to represent a sound, never in a word), then the two dots can be replaced with a line and so, I guess, the lowercase T technique from the blog post could be adapted to it. I think I know what I am gonna do after work today

[brainwad]

There are such: Macrons are required in the Māori language, and probably other Polynesian languages written with Latin script.

[eru]

In German the Umlaut started as a quicker way to write ae, oe and ue. Perhaps develop your ideas from there?