Woah, camera rotation! Fog would add to the sense of exploration and I don't think would be concealing anything that's useful to the player (except if you have a "main path", but you could also indicate that in other ways). So I say do it.
I suspect there will be no "main path" :) but perhaps there will be some things to discover in the "leaf" islands, so I tend to concur.
Is the camera rotation too much for this kind of games? I tend to like it, but perhaps it's not necessary if I can keep the puzzle size in control (the other direction would be to add camera zoom).