Word of advice.

Don't split up parking lots into a bunch of tiny parking lots.  If you were going out out of the building you'd think "These 5 spots are a parking lot?"  No, you'd think the big rectangular section is one continuous parking lot.  Sometimes there are "Lot A" and "Lot B" that should be split.

It makes it easier to tag ownership, renders a bit better, and in GPS systems it won't show up a 5 different parking lots.

You can turn parking lots into MP (multi polygons) if you really want to pull out components that you don't like, like the island/separators.  You can also map individual parking spaces but I recommend doing that in JOSM with the gridify plugin.

Yes, OSM gets into a lot of tedious debates about what noun means and you'll run into classification debates like this constantly.