Creating a new D&D world, part 3

I recently purchased The Ultimate RPG Game Master's Worldbuilding Guide: Prompts and Activities to Create and Customize Your Own Game World by James D'Amato and it, and going whale watching, inspired me to create a new D&D world. So here we go! I'm going to use prompts from the book to begin crafting this world, but not all posts will be from there. These questions will pertain to the small island on which the adventure begins.

You can read part 1 of my planning here and read part 2 of my planning here.

Here is how I imagine different species of humanoids in the world. Note that all have a similar lifespan of about 100 years, otherwise, you can trust D&D Beyond's descriptions (though feel free to ask me if you have questions):

• Aarakocra
• Very rare and often keep to themselves because others are eager to use them for their flying abilities
• Typically live on the small, closer-together islands in the west
• Often employed as messengers with water-proof pouches
• Aasimar
• Very rare and often keep to themselves because others are eager to use them for their flying abilities
• Typically live on the small, closer-together islands in the west
• Often employed as messengers with water-proof pouches
• Air Genasi
• Very rare and often keep to themselves because others are eager to use them for their ability to hold their breath indefinitely
• Typically live on the small, closer-together islands in the west
• Often employed as messengers with water-proof pouches
• Dragonborn
• Rare, but they are especially respected for their connection to fire and warmth which is often coveted on the dreary islands
• Typically live on the larger, farther-apart islands in the east
• Dwarf
• Common, hearty folk most commonly found living on the rockier islands
• Found on many islands
• Earth Genasi
• Uncommon, renowned for their ability to travel quickly across rocky shores
• Found on many islands
• Often employed as farmers
• Elf
• Common, most commonly found living in or near the forests of the islands
• Found on many islands
• Fire Genasi
• Rare, but they are especially respected for their connection to fire and warmth which is often coveted on the dreary islands
• Typically live on the larger, farther-apart islands in the east
• Gnome
• Common, most often found living near the sandy shores of the islands
• Found on many islands
• Goliath
• Rare, hearty folk who live on the most mountainous of the islands
• Found on many islands
• Often employed on larger ships due to their strength
• Half-elf
• Common, an easily adaptable folk 
• Found on many islands
• Halfling
• Common, most often found living near the sandy shores of the islands
• Found on many islands
• Half-orc
• Rare, hearty folk who live on the most mountainous of the islands
• Found on many islands
• Often employed on larger ships due to their strength
• Human
• Common, an easily adaptable folk 
• Found on many islands
• Tiefling
• Rare, regarded with superstition because of their heritage
• Typically live on the larger, farther-apart islands in the east
• Often end up on careers on the outskirts of society
• Water Genasi
• Uncommon, viewed with a mix of superstition and awe as they can breathe underwater (some admire this, others mistrust that they are more tied to the dangerous seas than their home on land)
• Typically live on the small, closer-together islands in the west
• Often employed as messengers with water-proof pouches

(Prompt by me)

"Humpback Whale (Megaptera novaeangliae)" by V.L.