I don't think Puerto Rico statehood has anything to do with pursuing more diversity. The fact is Puerto Rico has been in part of the United States since the 1800s. The people there are US citizens and have expressed a desire to have their territory, which is already a part of the United States become a state.
I think people are getting hung up on the differences and commonalities with statehood vs. territory. The United States of America is the country of which we're all a part of. States are subsections of The United States of America. Washington, DC is a subsection of The United States of America. Finally the US territories are subsections of The United States of America. Everybody born an any of these subsections are equally American citizens. The only difference is the role of state governments vs. territorial and district governments in the US Constitution, which has absolutely nothing to do with the status of the people living there.
-States send US Senators to Washington while the territories do not.
-States send Representatives to the House while the territories do not. However in efforts to be more inclusive without changing the constitution the district and the territories eventually were allowed to send 'delegates' to Congress who do everything a Representative to Congress does (chair and serve on committees, introduce bills, argue for or against bills on the floor, conduct hearings, etc.) The only thing they can't do is vote on bills in the full house (but they can in committee) and they represent their whole territory regardless of population, not congressional districts.
-States can send Electoral College Delegates to Washington to select the POTUS.
-States can participate in amending the US Constitution.
-States get their own star on the US Flag.
Territories have the equivalent of state legislatures, a Governor and Lt. Governor, their territory's National Guard that gets called up and sent the Afghanistan, etc. US currency is used. The people have US Passports. People there can appeal their court cases to the US Supreme Court. Its just like living in a state as far as being American goes. The only difference for the people is statesiders can vote for President but only because of the Electoral College and the fact that all of the state governments eventually gave their citizens the authority to vote for President when it was originally done by the state legislatures. Also important to understand, if someone from one of the 50 states moves to a territory they become residents of the territory and no longer can vote for President.