Rice or grain pack from Mali is worth adding because it feels like something you actually noticed while travelling through Mali, rather than a generic souvenir. Grains, pasta and rice are not glamorous, but they are useful, cheap and often taste different from the UK supermarket version. 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.