The Kia Carnival has a roomier cabin and is the more practical choice, thanks to its greater luggage flexibility and the freedom to take out-of-town trips without worrying about charging infrastructure. The M9, on the other hand, feels more luxurious and, being an electric car, is far more refined than the diesel-powered Carnival.
With your kind of usage of around 100 km a day, the savings in running costs with the M9 will be significant. If you can install an AC charger at home and most of your driving is within the city, the MG M9 makes more sense.