I've always wanted to write a novel about what would happen if aliens came down to visit us. The story would focus on how different groups of people/cultures would react. Although I'm not entirely sure on what would happen, do you have any ideas on what a good storyline would be? Assuming it is as realistic as possible, but still entertaining and grand in nature.
Yes! Here's an example idea for a plotline for your novel:

Title: "The Earthbound Visitors"

The story begins with the discovery of an extraterrestrial spacecraft on land near a small town. Local authorities quickly begin to investigate, leading to a number of unusual events that occur over the next few weeks.

    One group of locals believe that the spaceship is from another planet, while others fear that it could carry some sort of infection or virus that could harm them. As the news spreads, tensions between these two factions grow.

    Meanwhile, scientists around the world are working to analyze the spacecraft's technology and determine its origin. Some experts believe that the vehicle may represent a new form of communication with alien civilizations, while others suspect that it could contain advanced weapons capable of devastating humanity.

    As the investigation continues, unexpected events reveal that the ship is not alone - it has arrived carrying an ambassador from another civilization. The alien offers to help solve the mystery of the crashed spacecraft, but many of the local citizens remain skeptical.

    Over the course of the next several months, the residents of the small town come together to discuss the possibility of an alien presence and how they should respond. Some argue that there is no reason to fear the visitors, while others express concern for the impact such an encounter might have on their way of life.

    Ultimately, the decision to welcome the alien guests becomes a personal one for each resident, and the outcome will shape the future of the small town forever.

This plot outline provides a starting point for your novel, and you can add additional elements and twists based on your own experiences and imagination.