The conclusion I have is that the NatPop route is mostly a AI thing, because it is extremely fun to go for the president German and attack the Chaco and Chile right in 1936 and build a Great Bolivia, but after that everything turns into something very slow and your army with all the bonuses cannot surpass 100 thousand men with the limited conscription. I think that Bolivia should have a focus to enact the 'Extensive conscription' or even the 'Service by requeriment', because I cannot enact any of these two without being at war with something with way more manpower with me, and I cannot challenge Chile at first if I don't start with some manpower advantage.
After the nationalists took over I spent 2 years to complete the political tree and open the invasions one, I delivered a massive decaptating strike by encircling most of the Paraguayan army at the Chaco Boliviano, and then just walked without combat into Assunción. Hearts of Iron 4 (HOI4) has had great modding support from day 1 of release with many mods, small and large alike, being released. At the first I couldn't fire the coup event, until I found out with a help of a friend that I have to wait until 1938. Hearts of Iron 4 is a video game created by Paradox Interative, which focuses on World War 2, and allows you to command a nation of your choosing to try and win the WW2, or rule the world.