Bruce Lee admired boxing a great deal and was actually a huge admirer of Muhammad Ali, I believe he incorporated a lot of his style into Jeet Kun Do (notice how Bruce was bouncing around ? Well). He admired boxing as an art form. He was also a huge admirer of Muay Thai and said that the swing kick was the most powerful kick he'd ever witnessed (that's where the 10000 kicks quote is from). He was a good man and dealt with a lot of racism within his own culture because he was the only dojo that trained and allowed black people and white people to train in (many of his best students were black). For that, they almost wanted to rebuke his licences and accreditations.
In a lot of ways Bruce Lee was perhaps the first mixed martial artist, Jeet Kun Do was unfinished and it was Bruce's plan to create a fluid form of martial arts and a way of life. The movie Dragon: The Bruce Lee Story is a great movie to watch as it follows Bruce's life, it focuses more on the premise that he was running away from a family curse that took his father. While there are many conspiracies as to what may have happened, many doctors suggest that the combination of hashish in his stomach and the sleep medication they gave him may have caused an allergic reaction that caused his brain to swell and in the process ended his life. Bruce was known to chew cannabis after meditating and no it wasnt what killed him he chewed cannabis hours before.