Macadamia nuts is worth adding because it feels like something you actually noticed while travelling through Kenya, rather than a generic souvenir. I would buy a couple of packets: one to open while travelling and one to bring home unopened, because snacks have a habit of disappearing before the flight. I would look for it in a proper local supermarket, covered market, deli, pharmacy, gift shop or small producer rather than leaving it until the departure gate. Back in the UK, it is worth checking specialist shops first because they often stock a better version than a broad marketplace listing. The ideal version is modestly priced, not too bulky, and good enough that you would buy it again even without the holiday memory.