In a 'dr manhattan x reader fanfic', the setting could range from the post - apocalyptic world of the Watchmen universe to more contemporary or even alternate settings. The relationship might be one of admiration from the reader's side, as Dr. Manhattan represents an entity beyond human comprehension. It may also explore themes of power imbalance and how the reader tries to bridge the gap between their mortal self and Dr. Manhattan's omnipotent being.
At the moment, there's no definite information about more Dr Stone manga. It could happen if there's enough demand and the creative team is up for it. We'll just have to wait and see.
It's hard to say for sure. The decision often depends on various factors like the popularity and sales of the original series, as well as the author's plans and the publisher's strategy.