qualitative research methods

I'm currently writing an essay on "the strengths and weaknesses of qualitative method in researching contemporary religions and spiritualities". It's really difficult to come up with more strengths than weaknesses. Is this because humans are an inherently moany species, constantly finding fault with everything, including good old qualitative methods? Or is it because the strengths are a general thing and the weaknesses are very specific?

It's also difficult to find citations (especially ones dealing with qualitative methods in the study of religions), because journal articles are normally reporting on what the researchers studied, rather than evaluating the methods used (though they usually say what methods they used, they obviously want to tell you how wonderful they are, not to criticise them).

It's also difficult to review the whole field of qualitative methodology in 1500 words! I need at least 2500 to really get my teeth into an essay topic.