That would be awesome; some groups have very similar colors, so it becomes a bit hard to tell which is which without having to go to the location itself to find out.
But, I've got a question, the Los Santos turfs are made out of clusters; when you get one you actually get a bunch of them, how would this work for this system? Should you see the group's name for each square, or by cluster? Maybe the name would show up in the middle of a cluster, either way would work, but since Los Santos has a lot of these little square turfs, there would be a lot of text, could be confusing. Regardless of that, my vote is positive, as you said, this is harmless and would be very useful; there is no reason for anyone to vote negatively.
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