Some proposed ideas about text editing improvements

Automatic capitalization when editing paragraph

That's going to be a major project unless you intend to limit it to automatic capitalization of the first word in a sentence, then there will still be challenges when the language used doesn't have capitalization like Japanese or Hebrew.

FWIW, I can't imagine anyone being so bothered by the need to hit Shift to capitalize the first word of a sentence that it could possibly be worth the effort to implement such a feature (and the controls needed to turn it off, which many of us would immediately want to do).

Everything else makes sense to me. Bullets probably the least important on the list, before that I'd think about things like basic indent controls

As it says in the project description, MuseScore is not a word processor, nor should it attempt to replicate all features of one. Adding more features increases the burden of maintaining backwards compatibility in the file format and consistent rendering between platforms.

All of your suggested features can be faked using existing formatting tools:

• word wrapping can be done manually by adding line breaks
• justification can be done by adding spaces and changing their font size
• line spacing can be done by adding extra lines changing their font size
• bullets or numbering can be added manually (e.g. with the unicode bullet character "•")
• tab indentation can be done with spaces

See the inside covers of scores in the OpenScore collection for examples of these workarounds in action.

I suggest you restrict yourself to looking at features where the workaround involves a particularly large amount of effort, such as word wrapping and justification. These are the ones that are a major pain to do manually, especially if you want to change the text or layout later on as it requires going through and adding new line breaks and redoing all the space adjustments again.

I would add one more thing that isn't on your list: clickable URLs.

By the way, many of these text editing features are available in Qt. You should compile and run the Text Editor example application included with Qt (you can find it from the Welcome screen in Qt Creator - see Qt Examples).

I believe that MuseScore used to make use of Qt's text editing facilities but this was disabled at some point to reduce complexity, so now only basic text formatting is available. Perhaps somebody who knows more about this can comment.