First up, congratulations - this is a fantastic read so far! And so very different from any other Ryukyu AAR's.
I was about to say that you have to attack since you're running out of time, then I realised this isn't a specific WC attempt. I don't think Bureaucracy is a good National Idea, if you want to focus on your economy I'd take NTP and start trading (what are your sliders like for trade? Couldn't see in any of your pictures). At this stage your main threat is the colonial powers, Castille especially looks very strong. If you want to not get steamrolled by them you need to expand quickly into Indochina. Besides, I think your economy is reasonably strong atm, and once the Makassar provinces core it'll get stronger. So I vote Plan A.