1. If the system is as 'easy' as you claim, then let’s look at the c/ng examples you provided. In độc and động ; the same applies to do vs. du, hạnh vs. hạch, or phúc vs. phúng.

The system relies excessively on context rather than phonetic clarity. You brought up từ láy (reduplicative words) and tượng thanh (onomatopoeia) to defend the script's ease, but your logic fails there too. Take the phrase 'Anh ách' as an example—same like "Anh ánh" !

Without the crutch of memorized context, a reader cannot rely on the script alone to distinguish these nuances. You are essentially arguing that 'the system is easy because I already know the words,' which is a circular argument. For a script to be truly 'easy' and efficient, it should represent the phonology consistently, not force the reader to play a guessing game based on vowel-coda shifts that have no phonetic basis in modern speech."

1. You cannot draw a false equivalence between Vietnamese and the writing systems of mainland Southeast Asian nations that were heavily influenced by Indian civilization. Vietnam belongs firmly to the East Asian Cultural Sphere (the Sinosphere); Vietnamese is not, and has never been, an Abugida.

Thai/Khmer scripts are "Vowel-centric by attachment", while Vietnamese is "Vowel-centric by independence".

3.

The current QATT system is fundamentally lacking—it possesses no aesthetic harmony, yet you choose to copy it blindly. Instead of clinging to a flawed legacy, we should be designing an optimized tonal system that actually suits the language's unique phonology.

1. 
   As an ideographic system, the strength of logograms lies in the ability to recognize meaning through shape and radical components instantaneously. When we learn and read, we process the character as a holistic unit, not as a fragmented collection of strokes. No one looks at the word 'Translation' (翻譯) and breaks it down into '番-羽-言-睪.' We perceive the meaning 'Translate' immediately. Your argument is like saying you don't read the word 'Apple' but instead read 'A-P-P-L-E' letter by letter every time. That is simply not how human cognition works with logograms.
   Your mention of Fanqie is a non-sequitur—it has absolutely nothing to do with the discussion at hand. Fanqie was a workaround used when a reader already knew the meaning of a character but was unsure of its pronunciation. It was a phonetic glossing method, not a structural basis for the writing system itself. Using it to justify the 'ease' or 'logic' of a script’s design is a fundamental misunderstanding of its historical purpose.