What is the general guidance on hinting to users that they should use a feature? It's always a shame when you design something really cool, and users miss it.
I think you are kind of right on this, for me the “really cool thing” is seeing the routs not the fly through. I wouldn’t be surprised if that was the same for most people. I think it’s one of those cases (which I have done myself, multiple times) when you build something and you think the best thing is this clever thing you built, and you love it, but actually the basic functionality is the “cool bit” most people want.
If it were me I would not have an auto play at all but a really big fat arrow pointing at the play button saying “this fly though is really cool”. Might not seem “professional”, but it works from experience.
Ha, I don't want to tell you you're wrong, but having heard from a lot of people on this, I'm not sure this is right. The vast majority of people I hear from seem as or more interested in the flyover than the routing itself. And that's why I have to strike a balance here.
I agree that I mostly want to see which rivers the drop flows to but really enjoyed the flight down the Savannah river and seeing how winding it is. Spent a week canoeing it a long time ago.