Out of my kids, Hamish is the one more likely to get along with Luke. Besides the Ravenclaw connection, he's not loud and he'll understand the muggle references even if his taste is geared towards other fandoms (hint: his boggart is a Dalek) and is not as passionate.
Cormac won't be a bully, per se, but he might mock a little.
Zoe is not interested in relationships at the moment, but Luke is definitely the kid of guy she'd go for if she didn't have her brother (and his Sisters) breathing down her neck. She'll be looking forward to facing him at Chess Club.
And Samir is... LOUD. He's more like a cat than a dog (well, a hyperactive cat) but I'm guessing Luke might still find him intimidating. They have Choir and Book Club together, so there's no escaping the Samir Experience.