The Vectran is the worst to finish without a cover.
It just turns to ash when you heat it.
I use a similar glue method.
I put a 1" long piece of heatshrink tubing over the line first,
then squirt urethane glue(marine GOOP brand) inside the end,
slide the tubing over the end and heat it.
The tubing squeezes the glue into the fiber of the line and solidifies it.
The tubing usually falls off later, but the end stays solid.

The superglue sounds like a great idea too.