Life has given Harry a lot of lemons: dead parents, a cupboard under the stairs, horrible clothes, Harry Hunting. The result should have been a downtrodden, sad little boy. It isn't.
"Blood of the friend, forcibly taken, you will resurrect your ally." Voldemort is resurrected. It doesn't go exactly like in the books. This is what happens when I read a bunch of 'good Voldemort, evil Dumbledore' stories, and then try to imagine what it would actually be like for a good Severus Snape in such a universe during the 13 years spent alone at Dumbledore's side.
You know those stories where Harry discovers he's super rich, super powerful, and all the good guys are evil and the bad guys are good and he's related Merlin? This story is nothing like that.
Everyone in the world starts their lives as betas. It takes meeting one's soulmate to spark the change into alpha or omega. Sherlock is a beta. He expects to live his entire life that way. After all, he doesn't have a soulmate, right? But if he did have a soulmate, he knew he'd turn out to be the alpha. And Sherlock is never wrong. Right?
Sherlock interacts with John and Mary's daughter, age two. Who comes out on top? A series of dialogue episodes involving Sherlock and Miss Watson. This probably wont at all be canon compliant, but until we find out what the series does with Mary's baby, we can pretend.