I agree. There is another tool I use already as a solo gamer, though it is also used for both group RPG games as well as solo and that is the MYTHIC Game Master Emulator.
Download for less than a tenner, has a Yahoo group. About half the folks there (when i was actively posting there were RPG types and the other half were wargamers. In the files, there is a complete 20+ episodes of a NWF game by one gent, and my unfinished new take on the Magnificent Seven. We all know how the story starts and what the seven were doing. I start with the premise that there's a story of what they were doing beforehand, and, things may not end up like the movie. For example:
1. Seven isn't a magic number - may be more, may be less.
2. Chris might not be the leader - at the start, he only promised the Mexicans that he'd put the word out.
3. Events could have unfolded differently - the funeral procession, the fast dray knife vs gun contest might have seen any of those three leads injured or killed.
4. Calvera might have had a gang that wasn't starving and poorly equipped.
5. What if the gang was larger?
6. Regardless of size what if the gang didn't have mostly mooks as the members?
7. What if there is a rival gang battling with Calvera for "property rights" on the town for some larger reason?
8. What if there were other candidates for the gunfighters besides the ones in the movie?
on those and other ideas, I started a project to retell the story. Have to pick it back up someday.
JJ