Hmm, I was thinking that, save for Chile which probably did the best of these countries up to the present-day, most of these places were screwed-over or at least suffering the most in the 1800's, making a PoD that simply removes WW1 a bit late. The earlier they get a start on things the better. What hurt most of them to the extent of my limited knowledge were ruling upper-classes that were either despised by the peasants or simply could not agree with eachother. The one exception would be Paraguay, because Francia killed or severely hampered most of the criollos, but Paraguay was screwed over by foreigners and one insane megalomaniac.
Chile just happens to have great mineral wealth... it's hardly an example of industrial development, as they import much of the industrialized goods they use from Brazil and Argentina.