In the end my final idea was an adaptation of the first idea. Instead of using people with t-shirts on i decided to use a sign with a message printed on it.
The message will be "Why Not Smile?". I decided on this message because i feel it will create a reaction without coming across too heavy or offending.
The main reason i chose to use a sign instead of people was because it was easy to move and it is the perfect size for obstructing someones movement path. You can still get past it but you do have to adjust the path.
This way of creating the intervention should help me achieve the results i want.
