Well, they might be really shocked at the power levels of Goku and Broly. RWBY characters are used to their own kind of battles, and seeing the insane energy blasts and transformations in the Goku vs Broly fanfic could leave them in awe. They might start thinking about how they could incorporate some of those powerful moves into their own fighting styles.
Some of the RWBY villains might be intrigued by the strategic elements in Red vs Blue fanfiction. In RWBY, they are used to battles with semblances and dust, but in Red vs Blue, the battles rely more on regular weapons and teamwork in a different way. They could analyze these new strategies and perhaps even consider applying some concepts to their own plans in RWBY, if possible.
One main element is his difficult upbringing in poverty - stricken surroundings. Another is the constant bullying and discrimination he endured due to his physical appearance. And of course, his strong bond with his sister Daki. This bond was what drove him to protect her at all costs and also influenced his actions as a demon. For example, he would go to great lengths to avenge any harm done to her because of their shared experiences of being outcasts in society.