This might be your first time eating an Onam Sadhya. There is Onam Sadhya etiquette you must follow. While the meal looks haphazard, understand each item has its place on the leaf (and will find place in your stomach) and has been specifically engineered that way.
Though it does not seem like much engineering is involved in Indian food, there is only spice and in the case of South India, rice. The rice does play a core role in the meal and on the leaf. Literally it is in the centre. Eat it with Sambar, Rasam and end the meal with curd rice. See engineering. The curds eases the spiced palette and gut with its probiotic magic.
The rest of the meal serves it purpose too. There is the vegetables for nutrition, sweet and sour dishes for taste, and even the papadam for the crunch which adds texture to the meal.
And you also eat off the banana leaf while sitting on the ground. Probably to stop you from getting up and walking away from this very large, seemingly never ending meal.
Learn the Onam Sadhya etiquette and follow the easy steps. Now you know what to expect.