Rw2
As I understand it, "Islandhall" is Eilean Choraidh in the shelter of Loch Eriboll. It's also been unihabited for over a hundred years but was sheltered and fertile enough to provide homes and a living quarrying lime for about three families. It was finally abandoned in the 1930s. While very slightly smaller than Eilean Hoan, its location is more hospitable and there were townships by the lochside that could be accessed by boat within minutes. This is the island -
While close to the shore, the currents round it make Eilean Hoan difficult to access. Also the beach opposite is very wide and exposed; fisherman preferred the shelter of narrower inlets. It formerly had one farmstead on it that was abandoned almost two hundred years ago, but it was still used for sheep grazing until more recent times. In the 1950s one of my uncles found himself stuck there overnight after missing the tide. As far as I know it hasn't been used for sheep for many years now. As you say, it's very flat and exposed to the elements. Enough of the old farmstead survives to provide rudimentary protection from the elements, but visiting is not encouraged and is certainly not for an inexperienced sailor/explorer.
There is a belief that the Norse, who called Loch Eriboll Hoanfjord, used the island to bury their dead. There is a smal beach on the south side facing into the fjord, that would be suitable for berthing a small boat.