I've thought of a request, which I might try and prototype if I get the time, but I thought I'd get it here for posterity otherwise.
In short, detach the process of building xpatch from the process of uploading the resulting binary from the board. Longer, whenever the graph changes, mark it as dirty. A background thread is monitors for dirtiness, and when it detects it, it generates code, marks the graph as clean, and starts building. When it comes to uploading, wait until the graph is clean and the builder thread is idle before doing so.
The idea of this is to reduce the latency of going live by hiding the build phase behind user interactions.
Cheers!
Lisa