Here are a couple of recent examples in which I picked single threads here and there. I'm really happy with these.
In this pattern, there is a row of three threads in the center, one silver, one black and another silver, single spots of color if woven in plain weave. I alternately picked the two silver and the one black as I went along.
It turned out much more interesting than if I'd woven it in plain weave. Simple. Nice.
In this one, I've put a single spot of yellow by itself and then picked it up only every third row.
In each of the following designs, I've pickup up some pairs of threads.
Only slightly more complex, this pattern has in it's center short bars of alternating colors in the center, 5 gold in one row, and 6 maroon in the next. By picking pairs of threads first right, then left, it gives the look of interlocking SS's or a Greek Key pattern.
For clear instructions on warp pickups with a host of great pattern ideas, check out Heather Heroldt's instructions here: http://www.heatherspages.net/uploads/6/7/2/6/6726652/beginning_alternating_pick_up_for_inkle.pdf