More complexity:
Varied CPU strength:
Maybe the CPU's could have different clock-speeds (setup in Custom play), and if you put a crowned process in a stronger CPU then it exits gracefully quicker.
Eg. a single CPU with 2x(3.3 GHz) & 2x(2.2 GHz) cores, for a total of 4 cores.
Heat management:
Another variation is that the CPU cores heat up over time when used, and if the core is cold, then it can overclock a bit & finish the process faster, but then it reaches "normal operating temperature" and clocks down to the regular process speed.
When a CPU-core is not used, it cools down.
so if you want a process to end really quickly, you need to cycle it though cold CPU cores in somewhat rapid succession. (maybe can be automated somehow? like a special slot you put a process in and it prepares the CPU for an boosted cycle automatically).