I am disappointed at one year (photo)

I had 2500 grafts done one year ago and the results are not what I expected. Will more hair grow if I wait another year?

At 12 months you now have 98+% of what you will end up with. I would not expect substantially more growth than what you presently have. If you had a competent and ethical doctor, go back to that doctor and discuss your disappointment.  If I were the doctor, I would want you to be happy and would do my best to make it happen, even at my costs to redo the surgery.