I agree with Viva2014, points granted for an MSc degree are 23, not 21. In his case, he will get 21 anyhow, because he does not have an MSc degree. The other post graduate diploma he holds does not qualify for the FSW class. Only the BSc will give you points (21). I do not think you have to re-take IELTS just to get 1 point more or 2 perhaps. You are above the threshold (6.0 on each band).
If you are not familiar with the CELPIP test, I wouldn't even suggest you to take it. Although it seems to be easier than IELTS, if you haven't studied the format of this test you me do worse than you did in IELTS.
As I said before, you may qualify for the 5 points of adaptability only if you have completed two years towards your PhD. Please ask your graduate office to write a supporting letter to demonstrate you have been studying full time for at least two years.
Good luck and hurry up, PhD stream will become inactive in January 2015.