After watching the keynote and the upcoming Meteor University I had immediately two topics that I think are super important and I’d love to see them in the future there, maybe even provide some material, too:
- Domain Driven Design with / for Meteor apps
- SOLID principles in Meteor apps
Why? Because this is the hot sh*t right now?
No, because Meteor is doing a super great job in providing architectural infrastructure (server, client, transport layer, package integration, build tool) that people have less to struggle with architectural design decisions.
At the same time, things like application design (classes, objects, functions, dependencies, coupling, design pattern) are even more in focus and many resources out there often cover classic MEAN/MERN stack and can rarely be applied to the Meteor way of designing things.
This would give people a real guidance in difficult times 
Other topics on architecture / application design, where I already tried to scratch the surface:
just my 2 cents on this one