Indonesia -
eat local street if you think your stomach can handle it, its more likely to give you the shits than street food in other SEA countries but its super cheap and delicious
street skating in jakarta is a lot of fun, therse also a park in north jakarta and tons of spots downtown not to mention gems all over the rest of the city. i'd say your best bet would be to meet some locals at the park and get them to show you some spots. another good place to meet locals is the skate shop kemang i forget what its called though, its across from a bar called splash though which is pretty sick and excellent for getting drunk. its right around the corner from kemang mcdonalds most cab drivers will know where that is.
tons of dope shit to see, volcanoes, jungles, beaches, islands - if you go to jakarta you can take buses and or trains to places like bogor, bandung, short plane ride to jogjakarta where thers also really nice outdoorsy type shit,