I posted an article on my blog, last November, that might be helpful to you.
Favorite Threads
Let me add that I prefer Ultra Thread 70 for collared jigs of 1/16 of an ounce or less. One-forty is my favorite for anything larger, regardless if collared.
Coats makes a strong 60/40 Nylon/Polyester metallic thread. The colors are promising. Here's a photo of some bass jigs I tied recently where both metallic and machine embroidery thread (trilobal polyester) are used.