My 2 cents worth, spend money on a good wheelset, keep the fork, as said, drop bars for tri competition unless you are thinking of aero type flat bars, leave the gearing alone if she pulls it well, like suggested above, for now and listen to the good doctor.

I understand the sentimental attachment but you are putting a lot of money into a non racing bike to use for racing, albeit triathalons. Optimally to me, the orange ST the doctor has shown would be what you want. YMMV.