Assuming you’re using the Pro edition, you can sort actions according to their Duration field. Actions with the shortest durations appear at the top of the list and those with no duration are at the bottom. Though, you would need to click on the action to see the duration for that action.
Alternatively, you could create custom perspectives that show you quick tasks, long tasks etc.
Including the duration at the start of the action and sorting by name would work as well. I recommend adopting a convention h:mm naming convention so that things sort in the proper order. For example:
0:05 - Respond to message from Tim
0:15 - Pick up parcel from UPS
0:25 - Clean Nuclear Fusion Reactor
You could even create TextExpander snippets for the durations you use most frequently to speed up entry on both Mac and iOS.