While I will say this was my least favorite of the series in terms of story, it is also the first of the series I actually did stuff in after finishing the story (I never did much side activities in 1-3, but after this I wanna change that). I've played for nearly 70 hours and I'm 9 trophies away from platinum (Ex-Hard, Heir to the Ultimate, Business Card, Heir to the Powerful, Amon Defeated, Star of the Coliseum, Master in Training, Weapons Master, and Way of the Pachinko King).
Most of these are just time consuming and aren't all that difficult (well, unless the game is insane on higher difficulty settings). I got over half of Ultimate Challenge done, but I'm stuck on some, and Kiryu and Akiyama are already level 20. I like to think I'm close to platinum, but I know I'm not. Hell, playing through the game two more times is gonna be every bit of 30-40 hours right there.
Think I'm gonna take a break, maybe get some more time with Yakuza 3. Maybe.