Photo Credit: Lucasfilm
The casino on Canto Bight.
When Rose tells Finn that Canto Bight contains the “worst” types of people, that is a nod to A New Hope, when Obi-Wan tells Luke:
"You will never find a more wretched hive of scum and villainy."
Finn is acting like a scoundrel, of sorts — like Han and Lando, where he can’t get enough of the casino, it’s excitement, and scenery. Remember, he was taken from his home as a kid, so this is his first exposure to something this magnificent.
However, more than a new “Mos Eisley,” Canto Bight is used to stretch and grow Finn’s character. Rose inspires him to fight and not run. When Finn sees the oppression of the galaxy and the those who support, that has a lasting impact on him moving forward.
The drunk alien interacting with BB-8 believes that the droid is a slot machine. Those coins that BB-8 uses to help D.J., Finn and Rose escape were at that very moment.
The duo fails in finding the Master code breaker, but they do locate a code breaker, D.J. Come to find out, D.J. was only in jail due to the fact he needed a place to sleep, so he committed a crime to do so. On his cap in Aurebesh, it reads “Don’t Join.” Also in Aurebesh, it reads “CBPD” on the Canto Bight Police helmets.
The stable boy with Force powers, Temirir Blagg, was in a previous Rian Johnson film, Looper. He was the youngster with telekinesis, also having similar skills in The Last Jedi. Coincidence?
Rose gives the boy her ring, which has significance during the days of the Empire. The ring was used by those part of the delegation for 2,000, Republic Senators who believed Chancellor Palpatine acquired too much power as the leader. Among that very group was Padme, Mon Mothma, and Bail Organa.
Once the Republic transitioned into the Empire, those 2,000 Senators remained loyal to the old ways, becoming Rebels. Those rings were used to communicate and recognize other Rebels loyal to the cause.
During Rose and Finn’s escape from Canto Bight, his ship explodes again like it did in The Force Awakens. Both D.J. and BB-8 steal a vessel aiding in their survival, with the droid doing the unexpected throughout the entirety of The Last Jedi.