Could your whole post be a very roundabout way to ask this simple question?
"Where did kanji, hiragana and katakana come from?"
Kanji (Chinese characters, literally "Han characters") came from drawings.
Hiragana also come from Chinese characters.
(Hiragana characters are underneath the red ones)
Katakana also came from kanji, they are simplified versions of them.
(katakana characters are on the left)
Your other question seems to be how our society would look like if we used characters instead of the alphabet.
It would probably be similar to what we have now and have other kinds of characters than the Japanese/Chinese.