I like the start even with the clichéd shopping trip and tons of money in the bank, at least you didn't linger over it. However, two questions, how old was the future Harry and why would sending his memory and power back change 14 year old Harry physically?
I agree with CJ in that letting the Dursley's see his new appearance wasn't smart unless he doesn't care what Dumbledore thinks. Also I like the idea of helping Sirius out. Hope you don't use Ginny but I like Tonks and Fleur.
In future chapters would love to see into his mental thoughts/emotions and more explanations and reasons.
Hope you continue with all your stories soon.