I feel that a lot of your discussion about Fun Theory is a bit too abstract to have an emotional appeal in terms of looking forward to the future. I think for at least some people (even smart, rational ones), it may be more effective to point out the possibility of more concrete, primitive, "monkey with a million bananas" type scenarios, even if those are not the most likely to actually occur.

Even if you know that the future probably won't be specifically like that, you can imagine how good that would be in a more direct and emotionally compelling way, and then reason that a Fun Theory compatible future would be even *better* than that, even if you can't visualize what it would be like so clearly.