Thrillers are all about resetting the world back to normal, but F/SF usually rejects that idea.
You cannot change the world without changing the character, and vice versa. Do it consciously.
Stories are based on the moment of change, but that works because a change is either called for or resisted, and the bit before the change can speak to which it will be and make it more resonant (while hopefully engaging the reader).
Alternative to the Bechdel Test: the Mako Mori (http://www.dailydot.com/fandom/mako-mori-test-bechdel-pacific-rim/) test. Does a female have a character arc that doesn't center around a male?
Look for source/inspiration material that others haven't mined.
If you're trying to subvert a trope, don't stick with the original trope toolong, or you'll lose some readers.
Consider wish -> wish fulfillment -> consequences. Don't necessarily need to show all the consequences, but is better if you can show the realization that they're there.
If it feels familiar - setting, character, plot, any trope that you want to use - try to step back, figure out conditions needed to make it work, and figure out under what logic/worldbuilding will that ring most true (instead of just using an established set piece). For example, a non-evolving medieval society exists because if you try to advance, people will come and burn your workshop down. That kind of thing. Examine and justify your tropes.
Everybody wants me to read Patrick O'Brian. Still.
California still uses irregular verb forms. Dreamt instead of dreamed, etc. How lovely!
If there is a lot of something allowed or prevalent (in a society, setting, genre, or the rest of the book), it's absence becomes much more striking. This is particularly noticeable if its presence in a genre is new due to relaxed restrictions (i.e. swears, sex).
Definition: "sales blurb" - a blurb from another author that goes in a letter to the editors you're trying to sell to. Not the same as the blurbs for the back of a published book.
Work on figuring out *actually* how long it will take you to write something. Budgeting time and being able to give accurate delivery times to an editor is GOLD.
Plot-wise, remember that climax != payoff (necessarily).
Books can be a pain and a misery to write, but years later you can look at it and enjoy it. Or they can be great fun to write, with no suffering! Keep your head on straight and do not link a difficult/easy writing process to the end product's quality/enjoyability.