Hate adjusting hundreds of keyframes in a complex animation? If you can build out your animation in a way where you don't need keyframes then you will be able to make adjustments that much quicker on a tight deadline. There are multiple ways to create animation in Cinema 4D without keyframes and they don't all involve scripting or complicated XPresso setups. The most exciting options may be C-Motion and FBX.
What are your favorite ways to automate animation in Cinema 4D?
Watch a previous Mograph Candy tutorial covering XPresso Systems Presets for animation without keyframes. http://www.mographcandy.com/blog/2014/1/26/xpresso-system-presets-action-timer-time-control-random-integer-and-rotate