The Legacy of Aethyros

I kinda want you to make a regression style story from scratch and I want a magic-based system of these elements: wind, water, fire, earth, lightning, light, and darkness. I would like for you to make two sub elements for those primary ones stated before. I want the rarity of people born with the proficient one or more to go up. There should be a 'coming of age' ceremony at age 16 and this is a more medieval timeline with kings and dukes. Also, there should be a Guild System where adventures go take on quest for the Guild to raise their rank. I will leave that ranking system to you. There shouldsystem to you. I here should be a fee to become an adventurer and certain class you have to take to see how good you are with your skills or blessings. With that in mind there should be a 'Big Bad Guy' end goal I should work towards. I want there to be monsters and corrupted monsters affected by something that makes them stronger and more dangerous. The currency should be in gold, silver and copper coins. I will leave the name to you. The world should be massive with a lot to exploration for me to defeat monsters and foes along with meeting new and cool characters. The magic is based off these elements: water, fire, wind, nature, lighting, light, dark. The magic is based of this energy called Aether and it flows through all things.