I think that ultimately a degree is important, once your flying career is over you need some sort of qualification to continue with. Now your flying career could be 1 year or 40 years it all depends on luck and the job environment.
I left school at 18 to pursue a flying career it has taken me seven years including 2 years of instructing but now I am 25 and in my first airline job. During my time as an instructor I have been doing a degree with the open university, I am 1/3 complete with 2 or 3 years to go. This is an option as well, to get a degree you don't have to go full time for 3 years. There are always alternatives, if like me the flying just won't wait then this could be a way to go.
At the end of the day it is your choice, I know many who are sucessful airlines pilots with or without degrees. I found that after my brain was kicked into gear with the ATPL ground school that the OU course work was a fairly easy going continuation of this.
