Re: Will there ever be a top 5 asian singles player???
Rest a bit easier-it's already happened.
Kimiko Date was ranked #4 in November of 1995.
Surely it will happen again in the future at some point. I do feel though that VERY top players (champions) usually have unique qualities, whereas Asian tennis players in general come out of assemly-line national tennis associations.
This will make it harder IMO.
Can a Chinese parent defy a national tennis association in China the way Richard Williams, Mama Hingis, or Yuri Sharapov did? Even stretching back to champions like Graf, Seles, Evert, Navratilova, or Mo Connolly, they all have one thing in common--they were driven by parents or coaches who either ignored their national association or told them to shove it.
Henin might be one obvious exception to this (was she nurtured entirely within the Belgian tennis association??), but even Justine has thrived on being at odds with people.
This just isn't an option for Chinese players unless they defect.
As for Japan---
Tennis historian Ted Tinling once said the Japanese would never produce a champion because they were great at copying good technique, but discourage individuality.
Good technique produces a lot of quality players, but tennis is an individual sport.