Add Thickness (or aribtrary overloads?) to BezierTo

I'm currently building a gameplay spline system on top of the Shapes Bezier functionality, and I'm currently looking into what the best way would be to carry additional data per-point. 

I noticed that despite the PolyLine supporting varying thicknesses, the BezierTo function cannot actually work take thickness inputs. It'd be incredibly helpful if it could, as it'd allow properly interpolated thicknesses. I can approximate it myself, but the result would be better if it was properly interpolated along with the colour.

In a similar vein (and this might be more difficult), it'd be incredibly interesting to be able to make the PolylinePoint class able to take arbitrary data, as this would open all sorts of doors for further integrations between Shapes and other systems.

I've taken a minute to look into whether I'd be able to extend this myself, and while I probably can with enough time, I'm not a world-shocking programmer and it'd take me an unreasonable amount of work, so if this could be worked into the stock version of Shapes, that'd be incredible.