Curve like Metaballs?

Hi

I have this cloud of points I've developped and I'm experimenting with it.

I've given it a proximity3d to join them up and now I'm wondering if it's possible to apply a variable pipe to the curves where the ends are thicker than the middle, but in a smooth way, so that the ends will look a bit more organic without 'seams' where the different pipes intersect?

I'm attaching the file of the cloud and joined lines.

Thanks!