I think you overestimate the amount of redundancy required for a usable writing system. For instance, Thai has a large number of confusable characters: consider

I think you overestimate the amount of redundancy required for a usable writing system. For instance, Thai has a large number of confusable characters: consider pairs such as คด, ชซ and ขฃ. [0] is an interesting exploration of letter shape in Thai — redundancy is good, so Thai people have invented numerous strategies for making letters more distinct. [0] http://wrdingham.co.uk/thai/tellthai_preface.htm http://wrdingham.co.uk/thai/tellthai_preface.htm