Maybe this is going to get a little away from traditional mechanics in FFG's SW RPG, but I really like it when beliefs matter to a player, and to the story as a whole. Hence, I developed this mechanic. And it may just be me fiddling with the mechanics out of speculation, but whatever; take it with a grain of salt. It's just an idea.

The goals of the system are to make a character's beliefs have a mechanical effect, as well as portray a slide towards evil, without actually using the Morality system, since my players don't like it. It can also function a bit like Duty, in that you want more.

Belief

Each player starts with two Beliefs. Each Belief is worth a portion of your starting value (see the starting Obligation and Duty tables), and consists of a single noble statement about what that character believes in, such as, "Protection of the innocent comes before the mission or my personal desires," or, "Desperate times call for self-sacrifice, not desperate actions of my own."

Using Beliefs

Each session, you may invoke one of your Beliefs, on any test to which the Belief is relevant, and may use it exactly like a Destiny point, except that you don't have to flip the GM a Destiny token.

The Belief Chart

The group's Beliefs are assembled on a chart, just like Obligation or Duty. Each session, someone rolls the d100 and compares the result to the chart. If the result corresponds to a character's Belief, he gets a +2 Strain Threshold for the duration of the session. If the roll turns up doubles, or the player whose Belief was selected agrees to it, his Belief may be challenged during the session. Since this may, potentially, be derailing to the GM's plot, I suggest this roll is made at the end of a session, looking towards the next session.

If a player's Belief is challenged, then during the session, he gains Conflict for any actions that go against his Belief, or even ignoring the way his Belief compels him to act when it is relevant to the situation. At the end of the session, he rolls 1d10 and compares it to his Conflict. If he rolls higher than his Conflict, his Belief increases by the difference. If he rolls lower than his Conflict, his Belief decreases by the difference.

Dark Beliefs

If one of a player's Beliefs is reduced to half it's starting value, then the group as a whole writes a new Belief for him that is darker, more self-centered, more cynical, and in opposition to his other Beliefs, such as, "I will protect my friends at any cost." This Dark Belief does not hold a value on the chart.

A Dark Belief may be used just like any other Belief to gain the benefits of a Destiny point. You may now use your Beliefs twice per session, but the second use must be your Dark Belief, if you use a second Belief. However, each use of your Dark Belief immediately nets you 5 Conflict for the session. If this Conflict causes a reduction in Belief, the reduction is applied to one of your regular Beliefs, not the Dark Belief itself.

If you ever remove a Belief entirely due to Conflict from a Dark Belief, you gain another Dark Belief, as before.

Filling Up The Chart

If the group's Belief chart is ever full, then all Beliefs' values are reset to their starting values. Furthermore, each player may alter one Belief to reflect them changing over time, or, as the benefit for the whole group, remove one player's Dark Belief and give him a new Belief.

Yeah, so it's a little odd, I'm sure, and a little FATE-esque, but what do you think? It encourages the challenging of Beliefs to increase their values, and no one is penalized for going dark, apart from the loss of a shot at +2 ST... Also, redemption is a group thing, which reflects the efforts of those closest to you reasoning with you and trying to save you, reinforcing the group dynamic. And lastly, it puts more narrative power in the hands of the players by giving each one the equivalent of a free Destiny point.