If you're relying heavily on your personal network I'd be worried that those 803 people were not true customers. Don't get me wrong, I think this is a great idea, but I'm wondering how you know that a 803 person sample size is big enough.

Also - could/would people click on more than one button once they found out they were non-functional? It could be that some features would be best developed in tandem with others.

We intentionally diversified the traffic as much as possible, exactly for this reason. Only a small portion of the traffic was from personal networks.

Repeat clicks are definitely interesting. It makes sense that once a button was clicked and found to be non-functional, that may prevent future interaction. But that first click still holds value. It'd be interesting to pull stats on how many unique visitors generated those click events.