This is a very difficult question to answer because it often depends on the paper and the quality of the secondary sources. Either way there should be a balance between your ideas and the secondary sources that at most should be 50/50. Always lean toward your own ideas.
The best way, in my opinion, to use secondary sources is when another author says something exceptionally well. Whether its a snappy comeback or some nice rhetoric, quotes can heighten your paper's quality because you can pick and choose the best sounding sentences to help your paper.
The amount of secondary sources is arbitrary depending on the subject. The greatest risk is that you overuse them, so the only way to use too many is simply quoting more often than using your own thoughts. This kind of question is most easily answered if the student comes into the writing center and has us look at the paper with the goal of solving source issues. It is very subjective.