I'm a planner. I didn't used to plan much at all when I was younger -- I'd get an idea in my head and away I'd go ticka-typing away . . . and then I'd wander off. I battled between wanting to be surprised by what came next, the action unveiling before my eyes as a Reader, but lacking significant goals, I'd wander aimlessly until I ran out of steam.
Now, I plan. I listen to music to get the emotion of a scene, let each vignette play out before me, unrestricted by plot expectations or character needs, and if it has enough potential, I find a way to lace it together with other vignettes, and in this way sort of patchwork-quilt my way through the story. Along the way I set up my significant markers -- what needs to be accomplished by whom and when--, to keep me always writing toward something. I don't lose steam this way, and can work on much longer pieces.
That said, I feel the most important element to envisioning a story is to define its message. At the core of the best stories is the kernel of something bigger, and it's around this kernel that all the characters and events revolve. For example, in my multi-pronged Skyrim fan fic (not yet writ), at the very center of everything is "love". Each character's growth revolves around a different interpretation and manifestation of love. Each is an opportunity for me to explore the concept of love in all its aspects. I have a Christmas story addressing the ways in which we defeat ourselves, and that we are the only ones who can take arms against our personal demons to improve who we are, and reclaim our happiness. My Dark Crystal tale explores the perspective of someone made to feel outcast, and their journey to owning what makes them special and different, and stepping into the strength that is recognizing "different doesn't mean wrong".
With these principles at the heart of my stories, any time I have a question about events ("If the
bre'ith fi bragh are powerful enough to maintain balance in the world, why do the
scions need to be activated at all?"), or a sudden idea for a scene ("I have this scene in mind for Swift where everyone joins together to defeat the Skeksis, and <Unnamed> is on the brink of death as a result . . . !"), that seed at the very center helps me find the most appropriate answers. ("Because there's another power at play, demanding the energies of the
bre'ith, leaving them none to spare for the "main conflict" of the first arc." -- "In order to illustrate Swift's evolution from outcast to well-adjusted, she must be the one to defeat the Skeksis and save herself -- anything less would undermine the entire message.")
Meditate on what's lurking in the heart of your story, what is it pushing the characters -- and you-- toward the conclusion? When you recognize it, the rest is like filling in the words to what you already know, and finding the best way to communicate that idea so others know exactly what you mean, and enjoy their journey along the way.
Also remember this: It's never been about telling an original or unique story -- originality is overrated, and "unique" is just a fancy way of saying "snowflake", which is pretentious and annoying. It's about telling a
compelling story. Readers will forgive even the oldest, most cliched and played out story if you tell it to them in a compelling manner, in a manner which makes them enjoy that played out story all over again.
And Khasrin: As far as distances in Skyrim go,
the whole map is about 14.3 square miles, which is necessary for sheer playability. The cities are much smaller than you know a city would be, being as the population of Whiterun, for example, is smaller than even the smallest farming township would be in any real world situation. Thus, you're forced to do a little creative interpretation. I did the same thing you did with regards to traveling from Solitude to Riften, so I'd have a good, if rough, idea how long I could expect the journey to take for my fan fic, but even if I REALLY pushed it -- taking breaks to eat, sleeping appropriately (at an inn if I could manage it), and walking to conserve energy --, it still only took a few days. This, to me, defies the distance implied within the game via the behavior and conversations of other NPCs. As far as I'm concerned, if you treat Skyrim as a genuine country (even of modest size), no one is going to give you a hard time about the times you allot to travel. I feel like four days is too short a time to get from Solitude to Riften, but two weeks isn't unreasonable.
If Skyrim is the size of the United States, and Solitude is in Washington State, with Riften down toward Florida,
it would take you about six weeks (42 days) if you were a machine moving at a walk with no need for food or sleep. I'm a stickler for research and details myself, but sometimes you have to recognize when game mechanics are going to mess with the simulated reality of your story.