I hope the best for you but I have to be honest and say that I don't think you have too much of a chance. Everything you said happened is all within the non-refundable ticket contract. I do find it interesting that you were not notified of the changes by email.
You will still arrive at your destination within one hour of your previous arrival time and they can change equipment and flight number at their discretion.
When it comes to pricing it continously changes.
I hope the best for you.