OP - I'm a little bit younger than you and have only been riding since last October, but have found that I have been able to get into a more aggressive poosition, as the flexibility has improved. If you have the ability to alter it yourself, you could try changing it one 5mm spacer at a time - ride for a while and then weigh up your options to leave it as is, or try another 5mm spacer - until you get to where you reckon you're at your most efficient / comfortable.

cheers