A map view which shows processor usage by land parcel. This helps to identify parcels where CPU-hungry code is running, to the detriment of neighbours: it's remarkably hard to spot where the MIPS are being burned if the tendency in smaller-holding sims is to make properties inside blank boxes and by making extensive use of parcel permissions. Someone could be developing (or leaving to run!) a replicator on my next-door parcel and I'd have no idea.
A "hog spotter" map with colour-coding so that no-load areas are blue, active areas are green, high-draw areas are orange and loops are brilliant red, would encourage people to be good neighbors.