Climaxes and Player Knowledge

[SilentMonkey]

For example, say your story is about an assassin beginning to feel guilt. The climax will be the choice to kill someone and accept that she is a killer, or let the target go and realize she's more than just a dog of the military. If a player wants to go on the "Changed Woman" route, the choices the player picks are the non-killer-y choices, and so you can figure in the end, she won't kill her target. Similarly, the "True Assassin" route's ending can be surmised. How can choices point to an ending without giving the ending away?

Don't frame them as "pro-killer vs. anti-killer" choices. Frame it as "loyal to military vs. disloyal to military" choices. Did the player tend to pick choices that supported the military, or did the player tend to pick choices that went against the military?

Just as an example, you can slowly escalate what the military asks of her over time. Maybe simple things like running supplies, espionage, whether or not she trusts certain people, and then maybe some where she starts to commit small, but justifiable minor crimes. As the story goes on, they will ask more of her until she is ordered to kill, at which time she either carries it out or gets cold feet and leaves the target alive.

Now, it probably wouldn't be very shocking, but that's not really the point. If the player makes those choices then that's the ending they'd want to get, so let them have it. Just make each ending unique enough to be worth reading. Reveal some other information that is a direct result of the player's choices (i.e., because you didn't kill the target, they tell you X, or because you did kill the target, you learn Y).

In the story of an assassin, no matter how much you try to make the MC likable, he/she is still a antihero. A vigilante or murderer to put it bluntly, who is taking the matter of 'justice' into their own hands. It's rare that one who lives that kind of lifestyle can just walk out and live happily in the end without any repercussions. They simply know too much, created too many enemies during their line of work, or eventually lose sight of the value of life.
Given the circumstances, the outcome can hardly become simple as staying or leaving.
What are the consequences of the players choices? How has the MC changed? Do they realize what their actions have caused?
If I were to write a story such as the one you gave an example of, I would make it clear which path the player is going down once the MC's personality has been established and the world they live in.
Route 1: The player cares deeply about the MC and their well being, therefore they wish for him/her to leave that life before anything happens to them. However I would remind the player that in this life, everything is complicated. In the end the MC and the player understands the wrongdoings of their actions and instead chooses to save a few lives before being cut off from the organization. The player thinks all is well until the organization comes to cut off all ties with the MC...permanently>:) Unfortunately the MC perishes but they die knowing they have done some good in the world, happy and with some closure.
Say after experiencing this end the player thinks "Oh no! What have I done! I should have listened!" "I have to go back and fix everything."
Route 2: The MC wishes to leave the life and feels they are stuck in a world of nothing but misery. If written well enough the player will understand in their first play through that perhaps it could be better to stay, or it's their second play through and they want the MC to come out alive. In the end the player chooses to stay with the organization. The MC is alive but has lost all hope, living their life in the shadows and constantly looking over their shoulder.
Route 3: The MC and the player likes the life, therefore they continue on being a no good assassin who tells themselves they are doing a good service>:)

This is where good writing in my opinion takes advantage of what the player wants.
The first route is bitter sweet, the second and third is somewhere in the middle. Then hopefully in some forum the players are arguing on which route is the best one.
There would be players asking "Hey, which route should I follow? Which one is the good one." In response they would get "It's tough to say. The real question is...what do YOU want?"
Certainly this would be a breath of fresh air for the regular and new VN readers.