That's quite a laundry list, Ian. Very thoughtful and we appreciate the effort. Your first three observations are doable, but unlikely. At least by either Peter or myself. The original crew peeled off years ago (our DHR has been around for 16 years) and only he and I are left actively updating the route. Fresh eyes are always welcome. We though about speed trees, but decided against them. In my case, given the computer I was using at the time, they absolutely killed my frame rates. With my new on, it might work. I had not seen any animated streams anywhere. If they are the DLS, could you point them out? As for the two-dimensional people, that would be Dave's (dmdrake) baliwick. He's almost completely removed from Trainz now and has given us blanket permission to alter/upgrade any of his content. None of us, however, have the original meshes for them.
In several spots, I added the details of landslips and earthquake damage. The entire Paglajhora region (Guyabara, through Mahanadi, and to Giddahar) is in constant danger of landslides due to rain. As for the road condition, I agree, but it would be a major undertaking to alter them now. Neither Peter, nor myself, plan on doing any further versions for future builds of Trainz. TANE is as far as it get for me.
The scenarios look interesting, and could possibly be worked on independently of any input from us. All a person would have to do is point the map KUID to the current version of the DHR for it to function. Everything you mentioned could be added to the scenario instead of the route. On one of the videos we used, there was indeed a train/truck collision that needed to be cleared and the track re-gauged for the train to continue.
Pretty much everything hinges on finding one or more individuals willing to devote years of their time to keep the route in shape.
Bill
EDIT: I forgot to mention all the roads would have to be mated with invisible roads in order to animate traffic. Plus, you'd have to add some sort of traffic blockers to make all the grade crossings clear when a train goes by (AND, there are a LOT of grade crossings which was the primary reason we didn't have animated traffic.