I asked The Google Machine about Thai vs. Indonesian food. Here's what I got.
Very interesting.
With approximately 6,000 populated islands and more than 300 ethnic groups, the food in Indonesia is extremely diverse, based on religion, region, culture and season. There is an infinite number of versions of home cooked indigenous dishes, with ethnic contributions of Chinese, Malay, Indian, Dutch, Portuguese, Arab, Muslim and Hindu etc. Popular is Javanese, Sumatran, Balinese. Compared to Thai, Indonesian cuisine is more complex, has stronger flavors, earthy, more fried, braised, heavy, spicy and served often at room temperature. Prominent ingredients are a large variety of herbs, use of similar local ingredients like citrus, coconut, palm sugar fermented fish/shrimp paste and sweet soy sauce.
On our next trip I plan to ask the restaurant Maitre'd whose cooking and their nationality. Then ask for their native speciality.