>>It should be utterly unambiguous and 100% phonetic. That means that if you hear a word spoken you know how to spell it and, if you see a word written, you know how to pronounce it other than for the question of which syllable if any is stressed.
And when dialects are added in... this “new” system self-destructs (think of listening to some inbred Boston native pronounce “park the car” as /pahk da cah/ . Standard orthography was put in place precisely to avoid all the duplicate spellings generated by dialects.
It’s been tried. George Bernard Shaw willed his estate to change the English language to a purely phonetic spelling but the administrators decided to apply his millions elsewhere.