One of the best things I have done for myself is taking the time to get a professional fitting for my hair. The person I went to in my area worked with me to determine the best color to match my complexion and face shape. She was able to customize the cap and I ended up with a piece that melts into my scalp. This means I can style it about a million different ways, including parts and ponytails.
You will spend more up front, but will have something that will serve you very well and will be really what you want.
As for human or synthetic, I went synthetic. Easier to care for and with quality, it is indistinguishable anyway. A good friend went with human hair when she was being treated for breast cancer. We became roommates so that I could help her through that period. I can recall the amount of work needed, but there were some advantages as well. She was able to style it...I mean honestly STYLE it with irons and such.
Once I am a few years in to HRT and my face shape begins to really set, then I will consider HH. Also, HH is expensive!