3. You can interpret any statistic any way you like to get the answer you were searching for?
Yes, to an extent.
This survey will become very valuable if repeated consistently every year, so that trends can be examined. As a one-off, it is difficult to draw a conclusion about the overall morale of the armed services (though I stand by my earlier statement that I think the results would be shown to be surprisingly good if a similar survey was done in a similar large organistion - BA for example).
Where conclusions can immediately be drawn is in the differences between the three services (which could be considered directly comparable), and in the consistently large differences between officers and enlisted men. Those are the two areas that should be addressed by defence chiefs.