I have a few rough story ideas floating around in my head and no idea how to develop them into full stories.
One idea I had was a sci-fi story about colonizers reaching a planet that had been scouted out to be excellent earth like planet only to find out that its in the middle of an ice age by the time they reached it to build their colony. No idea where I wanted to go with the story beyond that though.
Another story involves a great city in some fantasy world that has multiple rulers controlling smaller sections of the city and fighting each other and politically moving against each other, both openly and covertly, to try to gain control of the entire city. Only I don't think I could write out all the intrigue that this story would need. My mind just doesn't work good at that stuff I don't think.
The last story idea I have involves the idea of cyclic time and the coming of the "Age of the Gods" again. It would involve the modern era being destroyed and recreated into the world of old mythology with old gods being reborn and new gods being created fighting for control to shape the world for the next cycle.
This story involves the idea I've had in the back of my mind for awhile about a cycle of "ages." Namely the ages of gods and legends like all the old mythologies, the age of magic followed by the age of man where gods and legends and magic have lost their hold on the world and wait to be reborn in the next cycle.
The first two ideas might be just short stories, or collections of related short stories, but the last idea I would want to have a full novel trilogy to properly cover everything. Only I know I couldn't keep myself writing that long right now.