Also Simon Tarses, the Romulan/Vulcan medical tech from The DrumheadOthers include: Lt Nara (unnamed alien, engineer, Eye of the Beholder), Lt Daniel Kawn (half-Napean, engineer, Eye of the Beholder), Ensign/Lt Ro Laren (Bajoran, pilot, various episodes), Ensign Sito Jaxa (Bajoran, tactical officer, Lower Decks), Ensign Taurik (Vulcan, engineer, Lower Decks) and depending on whether civilian personnel count there's also Guinan, Mot and one of the Ten Forward waiters (both Bolian).
Data is an alien, from an alien world, not human.I am on season three of TNG, from what I can remember the Enterprise D is the flagship of the fleet, apart from real life, restricted TV budget reasons, this so called flagship representing a multispecies Federation has a crew complement of around 1000 personnel and yet apart from Worf, Selar and Troi every other crew person is entirely human.