Other Versions of Cesium & External Cesium Instances

[ctrlaltf2]

Hey all!
I've been using TerriaMap and have some questions about Cesium. So, first off: my understanding is that TerriaMap uses a patched version of Cesium in order to embed Cesium into the map properly and implement all features. My question is, what would it take to use a different version of Cesium, e.g. one of the more 'bleeding edge' branches in the main Cesium repo?

Second question: has there been any work to make the embedded Cesium viewer less coupled to TerriaMap? Maybe an iframe, external service, etc; something that could be 'hotplugged' with a new Cesium build without having to rebuild all of TerriaMap?
Thanks!