My argument is one in favor of being more flexible than the OP proposes, by introducing the idea that letter case isn't a universal or even frequent trait of similar writing systems, and that you can even call into question its utility.
As for modern Latin (Latin originally didn't have letter case, either; widespread use of letter case is a fairly recent development), most common doesn't mean best - how the "market share" of languages and writing systems evolves is a more complex topic (Nicholas Ostler's Empires of the Word: A Language History of the World is a good book). That means looking at and comparing with other examples is often useful.
It's a little like the reason you want to learn more than one programming language - it trains your ability to think about problems on a more abstract level than a single toolbox allows, and gives you insight into the strengths and weaknesses of each of your tools and how to apply them best. Even if you wind up only programming in a single language anyway. It also tends to make you less dogmatic and more willing to go back to first princples. Or willing to entertain notions like "just because this man isn't capitalizing his letters it doesn't necessarily mean he has nothing to tell me".
Agreed. One could argue that modern "design thinking" involves the creation and extension of non-alphabetic, visual language. Someone unfamiliar with modern logos (e.g. share icons) and UI conventions (e.g. "hamburger" icon) may view these symbols like they would view Egyptian hieroglyphics.
2nd-order cybernetics is about observing the observer, which includes observing the limitations of communication. Studying different languages helps identify the limitations of each, i.e the untranslateables. There's a great book on this topic (we need an equivalent for software), a 1300 page "Dictionary of Untranslateables".
"This depends on what one means by “untranslatable.” Cassin and her team believe that an “untranslatable” word is not one that cannot be translated, but rather a word we can’t stop trying to translate, aware always that we haven’t quite hit it, that it isn’t right."
That's a great comment. The thread about Unicode 7.0 last month had a long, interesting discussion about the new emoji codepoints vs. logograms and ideograms, with a range of opinions: https://news.ycombinator.com/item?id=7903877
As for modern Latin (Latin originally didn't have letter case, either; widespread use of letter case is a fairly recent development), most common doesn't mean best - how the "market share" of languages and writing systems evolves is a more complex topic (Nicholas Ostler's Empires of the Word: A Language History of the World is a good book). That means looking at and comparing with other examples is often useful.
It's a little like the reason you want to learn more than one programming language - it trains your ability to think about problems on a more abstract level than a single toolbox allows, and gives you insight into the strengths and weaknesses of each of your tools and how to apply them best. Even if you wind up only programming in a single language anyway. It also tends to make you less dogmatic and more willing to go back to first princples. Or willing to entertain notions like "just because this man isn't capitalizing his letters it doesn't necessarily mean he has nothing to tell me".