The 100-200# paracord like cordage sounds like it could prove very useful and be worthwhile for hip pack size kits, but it may not fit the bill for a true pocket size kit. It could be wrapped around other objects or the kit itself like true 550 cord, but it is not something I would personally put onto a sewing bobbin. It may also be a bit large for sewing & fishing. The inner strands may work well for sewing, but how about fishing?

The quest for the ideal all-purpose lightweight cordage continues. Specifically interested in the three options I posted on earlier. But thanks for the input!