Indonesia has a crazy strong position, massive growth potential, and isn't stagnating unlike most comparable countries (e.g. Brazil). Plus, they're on the equator, that's the best position for launching shit into space.
They're in shape good enough that they could project a new capital somewhere in Borneo.
And then there's massive mineral wealth they can get from Papua. Which is already getting quite nasty, with big mining moving in and natives making a fuss about it.
But most importantly, Malays have been a trade superpower before; there's also a Chinese diaspora that might come in play with taking over and moving stuff out of China in the future possibly, and their location is right on the main global shipping route. If they can start homegrowing their elite (or perhaps, if their growing power starts to get Singapore gravitating their way, and they just de facto take over institutions already there), I can see them as a potential future superpower.