Best advice, start early. There's no penalty for getting your application in early, but the later you wait, the more applications that will have already been reviewed. I had my PTCAS sent in september of my senior year and was already accepted to a few schools by early october... well before their deadlines were even close.
I'd say start your PTCAS a.s.a.p and if you are applying to non PTCAS schools, start filling out their applications as well. If you are just waiting on your GRE, when it comes in you can just enter your GRE information and click submit. You sound like you have the grades and experience, don't fall victim to 'waiting too long' and not getting in simply because the seats were already filled.