I'll forego recommendations I've already given you, though will still recommend for others to read Ashita no Joe, Battle Angel Alita and Hokuto no Ken if they haven't.
Anyway, Mobile Suit Gundam: The Origin is a very good choice if wanting a sci-fi war drama with morally grey characters. It's a lot more comprehensive than the anime series and movie trilogy it's based on and the coloured pages have some top tier art.
Monster is good if wanting a psychological thriller with a lot of character development and exploration on the nature of evil.
Real is a pretty good sports manga that explores the psychology of its characters well, though it does meander after a while and is currently stuck in hiatus purgatory.
Not sure if you've read Vinland Saga, but that's definitely a good historical series with complex characters that is rightfully compared to Berserk. It isn't quite as good as the Golden Age, but it's a lot more consistent in quality unlike Berserk that mostly fell off the rails after the Tower Arc (though the most recent chapters of Vinland have been pretty meh).
Rurouni Kenshin is very good for a Shonen series with a good historical backdrop, a mature character with a dark past that became rare by the time of the 90s and serves as a very well told redemption story. Its last arc isn't as good as the Kyoto Arc, though certainly isn't as flawed as a lot of final Nekketsu arcs tend to be.