I second NightHiker - a USGI poncho is big and heavy in a cargo pocket. And worse (in my opinion) it creates an uncomfortable swinging motion when walking.

Knots, I'm sure others will beg to differ, but in my opinion you only need to know five: 1. figure of eight (and a retrace figure of eight), 2. a bowline, 3. prusik, 4. double sheet bend, and 5. square knot, you can do just about anything that needs doing with rope/cord/string. To learn how check here.