On alternate 2 there, an option would be to include the addr:flats key
). That seems like a
good way to represent big apartment blocks, like 53 Cook St in Auckland,
which doesn't render very nicely - at lower zoom levels (17-19) you get
a random selection of numbered units which looks pretty cluttered, and
you can't see all of them until you're at a zoom level of 21 or higher
The downside of that approach seems to be that searching for a unit
number doesn't work (in Openstreetmap.org and OsmAnd at least).
I'm leaning towards a mixed approach - show all the nodes (spaced out)
for less than about 10 units (or whatever number fits clearly in the
building footprint at zoom level 18), and a single node with an
addr:flats key for larger apartment blocks. What do you think?