Kevin, you can use any f-stop on the lens and not worry about a degraded image in most cases. The problem with f64 etc. often comes from the lens manufacturer's data sheets which can "see" a degradation of the image in the lab setting, but in terms of your eyes, there generally isn't a problem with most lenses. F22 is usually a good choice for most lenses, but movements may make this setting too shallow when depth of field considerations come into play.
About focusing, you need to be very careful that movements are done with moderation. The near-far focusing technique takes a bit of time to learn, but having objects with great heighth in the mid ground can be problematic. This is one reason I like the 125mm lens length when possible. It's a good compromise between angle of view and depth of field. Many times, no movements are needed from 12' to infinity.
That having been said, early morning is the time I prefer for shooting. Here in the desert, as soon as the sun comes up the winds start with the warming of the ground. Canyons need light, so this may not be possible in your area. A faster film will help, but give yourself time to learn. Large format has limitations, but the trade off in image quality is worth the effort. Take an even strain, my friend, and don't try to do it all at once. Small steps with pauses between for gratitude will help solve any problems which arise. The basics are important to learn, just allow enough time for the learning.