I have two of those giant cones of Precensia thread in beige. I have 50 weight for piecing and 60 weight for applique. I use both for bobbins and I use the 50 in the top for piecing as well. I also have the sew art invisible thread in black and white for applique. I had to branch out into colors when it came to quilting.
If you don't mind the look of it you can use the invisible for quilting and keep your thread collection small but I like all the decorative quilting. If you get 60 weight the color doesn't show up as much on the quilt top but you won't get little bird's nests. If you get 50 weight you can get bird's nests and knots if you're not careful but the color looks good on the top. Also, if you don't like using invisible, you'll need all the colors for applique.