Congratulations on your first Podcast Episode!
Building an original (RPG) World definitely takes imagination that is sometimes hard to conjure up. I think inspiration from previous creations is a good trick to creating a original world that has purpose.
One Dungeon Master I talked to who created original worlds/map designs gave me some clarity on the process for creating an original world and that really put things into perspective of how much effort goes into original creation.
Good luck with your future episodes!