Posting to bring this back to a) highlight it's still an issue and b) stop duplication of threads.
For me, the coloured overlay for each zone seems to appear either way over or way under the actual land, which means that depending on your level of zoom or your camera angle, you can be completely misled about what's covered and what's not. Now, if you have massive zones with loads of staff in each, it's less of an issue. But if you want smaller, more controlled zones, trying tightly to control your staff behaviour, it's an absolute nightmare - you might think you're painting along a certain pathway but you're nowhere near, or doing the next path over, etc.
It would also be REALLY great to have overlapping staff zones, instead of fixed boundaries. I might want, for instance, my entertainers to be in very small specific areas, whereas my janitors and mechanics may cover wider zones. It's quite frustrating to only have one or the other.
Staff management and zoning, if developed and deepened a little further, would go a LONG way toward improving the management experience of the game and to answer the critics who say it's just a sandbox (I disagree with them, but I'm certain we can go further).