This year we would like to place a stronger focus on the following topics:

Simulation, modeling and testing
Methods and tools for simulation and testing of blockchain behavior
Game theory and Mechanism Design
Fungibility
Enhancement of Scripting
New Validation Methods

We also welcome compilation/review of material on above topics made available to public since the last Scaling Bitcoin event.
Other topics of interest include:

Improving Bitcoin throughput
Layer 2 ideas (i.e. payment channels, etc.)
Security and privacy
Incentives and fee structures
Network resilience
Anti-spam measures
Block size proposals
Empirical mining data