The good thing is that if you can digest Branded to Kill, there are going to be a lot of great Yakuza movies to watch:Youth of the Beast (1963) The most traditional and coherent of the famous unofficial Suzuki trilogy, very digestible on a first view. Tokyo Drifter (1966) Suzuki basically makes an insane musical but with brawls and gunfights instead of showtunes - though there are some tunes in this one.For Suzuki, I'd also recommend Fighting Elegy (1966). It's not a Yakuza film but it has plenty of insanity and action. Pale Flower (1964) - One of my ten or so favorite movies. It might be the first of the quiet hitman subgenre. The B&W visuals are gorgeous.Sympathy for the Underdog (1971) Kinji Fukasaku was know for making bleak, violent no frills crime movies, but this one is a little more romantic or sympathetic (pun unintended) when addressing its leads - I think it's his best work and definitely one of the best Yakuza movies.Yakuza Graveyard (1976) Fukasaku's Battles Without Honor and Humanity aka Yakuza Papers series is more popular, but this imo is better, obviously more concise and is a great crash course into Fukasaku. Black Tight Killers (1966) If you loved Tokyo Drifter, this is a good companion piece. The best of the (non Suzuki) colorful, goofy and insane Japanese crime movies. These aren't Yakuza movies but Kurosawa's High and Low (1963) is a masterpiece and for my money his best movies. The Bad Sleep Well (1960) and Stray Dog (1949) are his other (then) contemporary crime movies/thrillers. He was definitely a master but the work of his period films can be a little grating due to the acting and customs. To me, Kurosawa's crime movies are the way to go, and at the very least, the best introduction to his work.
I would give Tokyo Drifter another shot in the future, especially if you love Branded to Kill. Drifter is a token example of a movie that greatly improves upon additional views - the plot settles in a little better and the randomness isn't jarring.
I got around to watching Pale Flower and High and Low. Both are masterpieces. Pale Flower predated Le Samourai and looks like it MIGHT have influenced it. They are both similar as far as the subject matter and the Samourai Code. The director of Pale Flower said he got the inspiration for that film from a scene in " Odds Against Tomorrow". Pale Flower is just a gorgeous masterpiece. The cinematography, scoring and acting are fabulous.High and Low is just hands down one of the best crime/noir films I've seen. Again, you get a grittier version of the American Noir. The cinematography, plot and acting are just fabulous here.
Sympathy for the Underdog (1971) Kinji Fukasaku was know for making bleak, violent no frills crime movies, but this one is a little more romantic or sympathetic (pun unintended) when addressing its leads - I think it's his best work and definitely one of the best Yakuza movies.
I almost forgot this one. It looks interesting also. I will update you...