I did some searching and Muletape is used to pull cables through underground conduit. One of the sales sheets says that it is lightweight and is easily blown through conduit. So it sound like it is lighter/thinner than webbing straps I am normally used to. It also only comes in white. Polyester will not take a standard dye and from what I understand, it is very challenging to dye it. It is much stronger than regular webbing straps. I don't know if it is UV resistant since that is not listed in the specs. It is also a bit pricy since it only comes in large rolls. $329 for a 3000 ft roll and I can't seem to find a smaller roll.
I like your design and it looks like I'll have to use standard polypropylene web strap.
I have a question, if you had the option, would a thinner width have worked? Looking at Amazon, the bulk webbing comes in sizes ranging from 1/2" to 2".