resolution vs. "curvy-ness"

[calischs]

Hi there,
Apologies if this is answered elsewhere, but I couldn't find it. I'm working on a sankey diagram with ~1000 nodes and I'm running into a limit on the granularity with which the strand widths are computed. For instance, the image below shows some nodes where the granularity causes the black bars and flow widths to be mismatched:

A workaround to fix this is to pass in a larger height and width to the to_widget() function. This fixes the mismatch between the bars and flows (as shown below), but it doesn't scale the radii of the flows. This means the diagram now looks much less smooth, as the flows now consist almost entirely of straight lines.

Any ideas or workarounds? Is there a way to set the "curvy-ness" of a sankey produced via floweaver?