Now I am obviously a bit biased since those stories often come under the umbrella of alternate history. That being said, I can understand how their proliferation can be annoying to editors who act as the gatekeepers between readers and bad fiction (well, most of the time anyway). So if you are planning to write one of the three types of stories mentioned and want to be able to stand out, below are my suggestions.
Parallel Universes: Sheila Williams of Asimov probably summed it the best in the article by saying she would like to see more exploration of current theories. The multiverse theory has been in vogue as of late, but there aren't many works out there that have tried explaining it in terms a lay person can understand. Fiction is a good way to do that. On the other hand, you can also play around with some of the speculation scientist's have been making about the multiverse, for example, the different laws that govern the parallel universe. There is already precedent for this in Martinez' Daedalus series (which has a timeline where alchemy works) and Piper's Paratime series (which has a timeline where reincarnation has been scientifically proven). Some might dismiss those ideas as fantasy, but you can still have your own fun with physics in your universe.
Time travel: At Capricon I was on or attended several panels that discussed time travel in fiction. Of the many topics we discussed, one that stuck with me is that you rarely see an analytically look at what happens when a regular person goes back in time. Too many time travelers have it too easy going back to the past, quickly fitting in after only a few "fish out of water" moments. To survive permanently, however, in the real past and not Hollywood's misconceived notion of it, now that would be an interesting story to read. One that uses real historical data and what a regular person the present could realistically accomplish in the past. Also, don't treat people of the past as country bumpkins. For one thing it is insulting (they are your ancestors too) and for another it just doesn't make sense. Sure the Wright brothers probably won't know what to make of your iPhone, but when was the last time you built an airplane from scratch (or an iPhone for that matter)?
Steampunk: I have gotten a lot of criticism for the amount of steampunk I include on this blog, but suck it up, it is related to alternate history. There are, however, some ways to make it more palatable for alternate historians and editors alike. For one thing, why not mash up the genre with military SF? Not all military SF needs to take place in the future on some distant planet. Why not write a story on an old war where the combatants have more advanced weapons. I am not talking about Guns of the South by Turtledove, but steampunk inspired weapons that could have actually been built with some tweaking in the past. Take the American Civil War in a world where the Analytical Engine was completed and came into widespread use, igniting an earlier information age and fast technological growth, like what happened in The Difference Engine. Could the Confederacy have broken the Union blockade with advanced submersibles or would they be stymied by Union airship patrols? What would masters of modern warfare like Jackson and Sherman do with steam-powered war cars and clockwork artillery?
These are just a few suggestions from myself. How would you make the above story ideas stand out for picky editors?
* * *
Matt Mitrovich is the founder and editor of Alternate History Weekly Update and a blogger on Amazing Stories. Check out his short fiction. When not writing he works as an attorney, enjoys life with his beautiful wife Alana and prepares for the inevitable zombie apocalypse. You can follow him on Facebook or Twitter.