There are a lot of possibilities for a 3rd KB movie: You have the fact that Beatrix killed the only parent B.B. knew for her entire life (and screwing up her informative years there after), Nikita Green being the same age as B.B., possibly meeting up in a High school setting and planning a little revenge together, the fact that she didn’t kill Elle, but only blinded her, which she could overcome with the training she has received from Pai Mei, and with her wealth could get some artificial eyes or a transplant. You have the Acuna boys down in Mexico seeking revenge on Bill’s death at his father figure’s insistance, etc.
With flashbacks and dream sequences, all the characters can be infused into the movie.
In fact, Budd could even be brought back with a quick dose of anti-venom from Elle at the start of KB 3, (and allowing Bea to actually kill Budd, and properly cross his name off her death list).
No hate posts needed, just throwing out what could be made to tie up all the lose ends. ;D