I can see a unity in the show; psychology. and it is done without sacrifising variety, very good. (If that is your style? imagine Derren Brown bending a spoon... no, thats not unity.)
You can include the lie detector test, and then you can "influence the audience to choose the paperbags by suggestion" or something, (Im not familiar with the particular chance game you are talking about, but I'm guessing its something like that)
Q&A or psychometry, it would be hard to make a presentation around psychology, to keep unity if, again, thats your performance style, with a Q&A routine, but I think it could be done, same thing with a psychometry thing.
for the prediction, do you know what kind of prediction you would do? The classical thing to predict what will happen during the show, what the spectators names is, how old they are, what car they drive or whatever is a good ender IMO.
lol if Derren Bent a sppon he would imply that the spoon was always bent and that he just convinced you it was normal somehow. He'd probably wrangle up some video footage of him holding the bent spoon while talking to the spectator for them to watch as well.