With each example I have tried to outline what the investor gets back - at an emotional level. All films offer things such as "a signed copy if you invest $50". But the real, emotional, reason to invest is often different.
Type One: Super gloss for nerds
These films tend to be about the showmanship of cinema, they give you a chance to fund a spectacle. This taps into two emotions. The first is the 'being part of something bigger' feeling. This is the same emotional need that made rich patrons invest in large gladiator fights in Rome. You want to be part of something you could never do yourself.
The second feeling is harder to define. I can only call it 'a boasting of knowledge'. This is because you can follow the development of the film. Show it to people. And then tell them lots of details about it only you know. It is like the ultimate collectors edition. In a word, you can show off.
I think Linh Mai has done the right thing with his trailer for The Last Cause in not really focusing on the story and / or calibre of acting. Neither of the two emotions I mentioned above are gained from the story. It just has to look super cool.
Perhaps one thing missing for people who want to be part of something bigger and / or who like to get into the detail early is any pay off if and when the feature happens.
Type Two: A cause
These films aren't asking you to invest in a film, so much as you are being asked to invest in a cause. They are about an issue, a philosophy or approach to life.
Georgia's film is about Alopecia. As such, the people who invest are more likely to be investing out of an interest in the disease, rather than an interest in documentary films in general.
Here the emotional reason for investing is clear - it is about doing something. It is about getting a film out there on an issue, when perhaps there seems little else pro-active that can be done.
Whatever approach your film takes, I think it is wise to consider the emotional reasons why people would invest. What are the deep reasons why they would help you to make your film? Are you giving them the right things back to meet those emotional needs?
Are you giving the investors access to bragging rights, to cool stuff?
Or are you giving them a feeling of moving forward in a cause?
This is what they have really invested in. The film is just the method.