A bonus equivalent to one or two weeks pay, plus a few small gifts should be more than enough. A MacBook would be very extravagant. I would stick to giving cash as the main gift - our last au pair returned every non-cash gift we gave her (even a gift card lol).

We're giving our au pair an Uber Eat's gift card and a holiday bonus equal to a week's pay. We asked her if she wanted anything, but she never told us anything.