Arthur&Eames raising Harry Potter

So, I've resumed writing in the 'verse where Arthur&Eames (of Inception fame) raise Harry Potter as their son, Eddie Colmes (because Arthur's identity when he rescued Harry was a Colmes). Eames is Merlin reincarnated; Arthur is purely muggle (mayhap, he's King Arthur reincarnated; mayhap he's not. Eames doesn't care one way or another). For Inception, in fact, everything is perfectly canon. HP, of course, shall be turned on its head.

But I need an actualfax plot, I think. Should I do the plot from Sorcerer's Stone? Because Eddie doesn't care one whit about Voldemort. He'll probably investigate the forbidden corridor, charm the dog (without magic), and steal the stone within two weeks of being at Hogwarts. He has no idea he's Harry Potter, but his fathers are master thieves, and one of them is the most powerful mage in the world.

*hands* I've been fleshing out the backstory the past few days, and I already know where the story starts, if/when I post it. But I don't know what plot it should have. Anybody wanna offer suggestions?