Scott - I can't speak to your platelet condition, but I would certainly expect a knowledgeable discussion of the medical issues and sound advice from your surgeon. Whatever his recommendation is, obviously, sharing your own thoughts and concerns is equally important. I wish you the best in this difficult time, reaching a comfort level with decisions such as these, as well as preparing yourself and family for the surgery itself.
For what it's worth, I thought the stage you are at right now was the hardest part. I had my pre-op the Friday before a Tuesday surgery, and my valve decision wasn't finalized until then either. You know what, though....to my surprise, I left the hospital that day at peace not just with the decision, but with the surgery itself. I was strikingly more relaxed and finally ready for surgery. So, the next 3 days, I was able to just relax and focus on family.
By the way, a year ago, your surgeon did a early Tuesday morning, middle of September surgery that turned out pretty well. Yes, me. You are lucky, though, you get an extra half hour of sleep. I had to be there at 5:00!
You will be in the thoughts of so many here, and in all of our prayers. Look forward to hearing your progress, as well as your post-surgery thoughts and experience.