The place where Boba Fett beat up the aliens and stole the bikes was Tosche Station (where Luke wanted to go to pick up the power converters). In a deleted scene from the first Star Wars, they show Luke going there at the very beginning of the movie tp hang out. The two humans who were being bullied by the bikers were the grown up versions of two of Luke's friends from Tattooine.

The evil Wookie with the Hutt twins was Black Krrsantan. He's a bounty hunter they introduced in the Star Wars comic books that launched around the same time as Force Awakens. There was a Vader comic book where they introduced him, Dr. Aphra (an amoral archeologist who helps Vader), and essentially evil version of C3PO and R2D2. The characters were so popular that they've hung around until now.