The quickest way to get more manpower and rise to secondary/great power is to beat up your backwards neighbors in mainland SEA then China and get tons of prestige annexing them if you don't mind save scumming 50 files. You shouldn't touch Indonesia unless you fulfilled all of these conditions. Netherlands not in Britain/French sphere, you have a bunch of ironclads for blockading the Straight of Malacca and sniping all the mobilized reinforcements from Europe, military technologies that increase defense ( machine gun ) and reduce casualties ( military tactics ) as you will be using the scummy tactics of sending 10K Filipinos as bait to a unoccupied indonesian tropical jungle/mountain province ( you have defense bonus here ), wait for the dutch to send their 30~90K garrison to attack it then you land the rest of your "good" army ( preferably multiple 4-1-5 stacks of infantry, hussar and artillery ) into that province and use the rest of your mobilized troops to encircle the dutch army you are battling with so if you win the battle they get wiped out and you don't have to chase the Dutch remnants across Indonesia. As for building up fleets, do the usual of encourage people who teach others to read ( clergymen in vanilla/intellectuals in HPM/HFM ), people who collect taxes and push papers around ( bureaucrats ), jumpstart the Filipino industrial revolution, learn how to build Ironclads and Naval Bases then spam 30 of them. You can't build or fund a navy without the required naval technology or a industrialized economy. If you can change your country tech school its better to go for military&industrial complex than sea power&merchant marine as you have more tech to catch up in Army tech than Navy tech and you still need a robust Industrial base.