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.
At the moment, there's no clear indication. But you never know. Maybe if there's enough interest and the story has potential for continuation, we could see more.
It's a toss-up. Some people love the immersive experience of reading novels and getting lost in detailed descriptions. Others prefer the quick and visually engaging nature of manga. It all comes down to individual tastes and what kind of storytelling format one prefers.