The problem with Chinese characters is that they are idiosyncratic. For example, I orally tell you "mao mi": how do you write it? If you've never seen it before, your chances of figuring this out is very sad.
You claim that 90% of Chinese writing are phonographs. Perhaps this is true to the most technical sense, but to most students this is useless. Try taking that 90% claim into a Chinese language test at university. The teacher will laugh at you as you arrogantly think you can decipher the phonetics of characters just because you know the "radicals". There is absolutely no reliable system for translating radicals to character phonetics, because it's all just so messy and hit and miss.
I once did a little project where I looked for phonetic components of about 20,000 characters. More than 90% had a phonetic component, but most of those characters are extremely rare.
In the first 300 characters a learner would study, there were about 5 characters with phonetic components. Phonetics don't really start to make a difference until about 2000 characters in.
