Godot's high-level multiplayer approach makes it uniquely easy to create client-host and true peer-to-peer (P2P) models of multiplayer gaming. However, outside of local area networks Godot struggles to actually create these multiplayer models because it lacks any sort of NAT traversal. I plan to implement WebRTC. The WebRTC standard will be able to provide support to Godot's existing multiplayer in making these sorts of peer-to-peer games.
It will also make multiplayer viable in the HTML5 target platform, and allow for easy interfacing with non-Godot peers that use WebRTC. Additionally, the support I build for WebRTC will make it easy to later add WebRTC MediaStreams, allowing for in-game voice chat. (However, building MediaStream is less-often needed for games so is considered to be low priority and non-essential in my project. See project proposal for details.)