If I may make a suggestion...
While I think I saw here suggested already the ability to change the work area of a robot, I was thinking perhaps being able to assign a robot to a plot. i.e. the lumberjack, hauler, planter, digger, and gatherer of a tree farm are assigned to the plot of tree soil, instead of a radial area. (Even sweet would be both options.)
Either way, it is rather annoying, because it's easy to end up in a situation where you have trees being planted and chopped in an area, but no-one picking up the logs, or trees that could be planted and chopped in an area, but there's no holes to plant them in (see here).