I’d suggest Indonesia if you want to stand out a bit more - not as many students pick it, so you can bring something fresher to essays. There’s plenty you can cover on development strategies, structural change, and globalisation links if you’ve got the right stats.
That said, China is definitely the “easier” option since there’s a mountain of data and it ties into almost every syllabus dot point. If you’re after accessibility and clear examples, China’s the safer bet.
Either way works - it just depends if you’d rather stand out with Indonesia or play it safe with China. If you’re stuck for stats, I’ve actually built EconTools Pro, which has case study packs for both China and Indonesia (with up-to-date stats organised by syllabus). Makes life way easier when you’re trying to slot examples into essays.