You misunderstood me.
They do make sense in WRITTEN form, but you wouldn't be able to use these methods of WRITING words if you overheard an Arab speaking.
Think rōmaji for Japanese. "Senpai" isn't how Japanese write it. If you overhear a Japanese speaking, you'd write it in rōmaji (as best as you can) because you wouldn't be able to write it in kanji or katakana. Reading rōmaji is easier (and more intuitive) to you [1].
You have no idea how to type a certain language (sans Tradeband, because it's easy to decipher and write down in Latin), so for instance slime language is full of pops, squishes and blops.
Adding a new language that is written in entirely unreadable symbols misses the point, for it is not onomatopeic.
You'd have to latinize the language at the very least.
[1] https://en.wikipedia.org/wiki/Romanization_of_Japanese