What is the purpose for an project like wkad? Is it to boost urban vitality through art and culture, or is it to boost art by the intensity of urban lives? If it is the first case, the fact that all art scenes which are intreative with urbanism tend to fade and diminish would challenge us to conceive and construct extravagant public buildings which will be so difficult to remove in times when they are obsolete. If it is the second phase, museums in what we have encountered relate little to art production and cultural originality. They become simply places for presenting art and sufficate culture.
Michael's comments on organic growth and temporary construction is right on. I have posed a question during the Shenzhen Biennale, do we trust our judgment to the future? Not for us but for our children? The answer is obvious: no. But it is immensely difficult because the contemporary politics. Lack of human continuity and full of budgetary schedule simply prevents a very profound and simple intelligence. Therefore, it is hongkong's creativity to reformulate the political and financial protocols to succeed in this project. Political creativity is much more essential to hongkong's society! More than art. 
Rem's suggestion is not organically free of planning, instead, it is a specifically strategized gradual accomplishment of collision between each programs and multiplication between the old and new Kowloon. It is to plan a city first then to use Art facilities to facilitate the city. Therefore, enters the number 2 purpose, which is art stimulates city! Then Art will be in a process of fading or reinvent itself in time and places.