Not exactly essential but fun non the less, what about a breed option.. A certain combination of buttons lets u meld the data stored within two drum patterns and spits out a baby drum pattern with rhythm, locks and patterns from the first two.. carrying a little genetic code from each... or add in a random element and voila.. pure brainless beats galore.
PS stolen this idea whole hog from my Nord, which allows this kind of function in the patche editor.