I'm a belt and suspenders guy. I have a kicker motor, an anchor, and a paddle. The paddle is next to useless in fast moving water, but the kicker will handle a lot of things, and throwing out an anchor, even if it drags, will slow things down to where you have more time to deal with things that are happening.

The best thing is to make sure that your motor is well maintained, and running smoothly before you head into the big stuff. It's worth spending a little time making sure that you get gas from a good spot, that you've added fuel conditioner to keep in clean, that you've changed the water separator some time since you were married. I'm a little anal - on most rivers I'll start and warm up the kicker at the beginning of the day, so that I know it's ready to go in case of need.

Practically speaking, most of the engine trouble I've had over the years with all my boats started at the beginning day, when the engine wouldn't start, usually due to dead batteries. If the motors start and run well, then I know I've got fuel and electricity. Once the motors are warm, it's easier for them to keep running, and life is usually good.