I have never heard of a Westernized Cherokee state besides their old designation as a "civilized tribe." Has any good research been done on Cherokee life immediately before their removal by Andrew Jackson?
This is an accurate summary of the state of the Cherokee Nation in the southeast in the years immediately prior to Removal. The first Cherokee Constitution was adopted in July 1827 and established a Westernized government modeled after the United States. If you visit New Echota, in northwest Georgia, which was chosen as the capital for the new nation, you can see a reconstruction of the building that once housed the Supreme Court, the General Council (which was divided into two houses - the Committee and the Council proper), and the national newspaper, The Cherokee Phoenix while the new capital was getting established. The adoption of the Sequoyah syllabary around this same time greatly boosted literacy rates in the Cherokee Nation as well, and The Cherokee Phoenix was published in both English and Cherokee. The rapid Westernization of the Cherokee was one of the many factors that prompted the United States to pursue the Removal doctrine. During his first State of the Union address, Andrew Jackson cited Article IV, Section 3, Clause 1 (that no new state could be formed from an existing state) as a reason to force the Cherokee Nation and other westernizing Native nations out of territory already claimed by the States. No one really knew how to deal with new nations popping up within the United States. Jackson and the like certainly weren't entertaining any arguments that would have allowed them to remain where they were at the expense of the Euroamerican population.
For an easily accessible summary of how life change for the average Cherokee during the 1700s and early 1800s (pre-Removal), I always recommend Theda Perdue's Cherokee Women. While the focus is obviously on women, there's plenty in there about men too since changes in the lives of one sex usually results in and from changes in the lives of the other. This includes, for example, women being increasingly excluded from political engagement in their society as the nation westernizes. In general, though Theda Perdue's works are great and she has done a lot of work on the Cherokee during the Removal era if you're interested in more on that topic.