I might be induced to use Soft Touch super-flexible steel cable from SoftFlex, but dear god is it expensive...and I'd have to order the 100ft roll at least. Even with a coupon code this weekend, the 100ft roll of .10 is around $30. The 1000ft roll (which I should get) is around $200. That's a whole lotta Nymo, not to mention beads!
The braided line might work.
The problem I have with most fishing-line monofilaments is that they get brittle with heat and time. I live in Phoenix. I have been beading for 30 years. I have seen what 25-year-old projects made with Nymo look like, compared to 25-year-old projects made from fishing single-strand line. The latter, without exception, are too weak to use now, if not completely fallen to bits.