The presence of the Isle of Kerrera at the mouth of Oban Bay affords Oban sufficient shelter to allow it to have a waterfront, even if the island is only five miles long and two miles wide. It may not be that far from Oban but you can get different weather in both places at the same time. On a November weekend stay in Oban with friends, I discovered that for myself with us getting a soaking while it was dry for most of the time in Oban.
Kerrera may be near Oban but I doubt that it ever gets crowded on there. It's a true walker's paradise with views of Ben Cruachan mixed in with others of Mull, Morvern, Ardgour and Lismore. Only 30 folk live on there so you can find your own space with intruding on anyone else. That also means that shops are absent and services such as accommodation and dining are limited to a single establishment in the south of the island. As if to emphasise that this is a place for connoisseurs, we are talking bunkhouse accommodation here and not anything more luxurious.