One reason I'm looking forward to another Deus Ex sequel is the possibility of trust gameplay that's actually meaningful.
Too often, players are put in situations where the protagonist is asked to trust a character while being all but certain that character is indeed trustworthy. There's no real question that the character is trustworthy. There's not even a possibility that circumstances might remove power from the character to keep his/her promises. The character just says "trust me" and player automatically answers "sure".
It's nice to be surprised by betrayal sometimes. Players have to feel like they're really taking a chance in order for those decisions to trust to seem important.