I read these three articles:
The first of those three links is a rather long and helpful article that includes history and ideas for moving forward. I learned about an early uprising against Spanish colonialism, and some of the ways that U.S. colonialism has shifted toward PR over time. It was interesting that some of the early leftist organizing on the island opposed independence because of a perception that U.S. had stronger protections for workers.
The other much shorter articles were also quite interesting. In the second, I learned that president of Nicaragauacedes his time to the author of the first article--Ruben Berrios Martinez, the head of a Puerto Rico Independence Party. This happened at a meeting of CELAC, Community of Latin American and Carribean States, and caused a stir because only heads of state usually get to speak.
The last article gave an interpretation of a recent vote in Puerto Rico on statehood, independence, or continued Commonwealth status. Apparently some claims victory for the statehood vote, but this author argued that it showed most people support some form of independence.