9005 Assessment
Abstract Fine.
Research Question One might reasonably say this is very clear or rather unclear.  The goals of the project are stated several times in the draft proposal, and they are lucid and sensible in each place.  There is one fundamental problem.  As now written this could be a proposal for five or more years of research.  It is well-conceived and worthy research.  But this is simply too ambitious as now written.  So, we need to find some narrower focus for the initial project for the MA degree.   Of course, there is some sense that the focus will be on the changing role of education over the past half century and its affects on mobility, which is a good start, but even this is a rather general.  Once we open it up we have to contend with varied kinds of mobility (educational, occupational, income); the complications of variations by gender, urban-rural differences, party connections, etc.; distinguishing structural from relative mobility in such a fluid historical environment; and so on.  Think of dividing the overall research agenda into stages, and then perhaps the first stage into sub-projects, where the aim is to start with a good sub-project of the first stage.
Literature Review  The literature review is well done.  It does a good job identifying how the existing research on inequality and mobility in China handles the big questions about changes over the past half century.  Once the proposal presents a narrower focus for the initial project, the literature review might need revision to take this narrower focus into account.
Data The data appear to be the best possible for the goals.  Undoubtedly, increased knowledge of the data will reveal some unexpected problems.  However, chances are good that it will also reveal some unanticipated opportunities.

Once the research question is more narrowly focused, it will be easier to choose the specific method of data analysis.

The EGP "class" schema mentioned toward the end of section IV can be useful, but it may be early to be deciding its value for this project.  Yes, it could possibly be applied to assessments of intergenerational occupational mobility in China.  But its value will become clear only after looking some at the empirical data, considering possible differences in the implications of occupational categories in China, possibly examining relationships between occupational categories and both education and income, and considering the implications of the dramatic historical changes over the research period.  In short, the EGP strategy is worth considering, but look at it critically in the context of the research, data, and historical reality.
Causal Interpretations The causal discussion is located in several places in the proposal, which makes it a little disconnected.  Still, the grasp of the literature and the arguments made are consistently sound. 

One note: I question the concern (section III, last paragraph) that education and class position have a two-way causation because people choose educational goals in anticipation of the practical advantages.  This seems to confuse relationships between variables with causal relations.  Of course, class origins influence educational achievements, but that is cross-generational.  Also, what is perceived as attainable and desirable will always influence choice patterns, but that is also something else.  Here it may be helpful to recall the importance of causal mechanisms.  
Research Value The proposal makes the case for the project's value, but this might be stated in a clear, simple, separate statement (which will depend on the decisions about a further focus of the research).
Timetable Well, the schedule is fine if we ignore the ambition of the project as currently described.
Citations & Biblio Citations and bibliography are fine.
Quality of writing The writing is okay.  The proposal could use a bit of editing for occasional, minor glitches.  Also, it might display a tendency to write overly long paragraphs, but not to a level that is problematic.

(Minor note: While “researches” is formally a correct plural noun, its [fairly rare] use as such is generally limited to circumstances where the research acts are considered "countable", as in "Janet's researches into her cousin's habits over the years"; when referring to the work done in an area, we usually use the collective singular version of “research” as in "the research of many scholars on class origins".  Usually, if we really want to use a plural form, we use a different wording, such as "many studies" or "many research efforts" or "many published research accounts".)
   
Priorities for Revising for Final Draft Setting aside the ambition, the proposal is developing very well.  The main priority would seem to be narrowing the project to a clear focus, along with getting some experience with the data.  
Miscellaneous Notes