I was in Iceland last week, and pretty much agree with all that. I did take my Wista, and (I hope) I made some jolly nice shots, but wind is definitely a challenge - so similarly, most of my photos are 645 plus x and portra 160. We did a couple of super jeep tours, and I recommend them because you learn a heap about the country from the driver/guides, and as well as the regular spots they may drive you weird places - for example, one driver took us to this bucolic farm in the middle of nowhere to wiggle our toes in a makeshift warm spring, another drove us through private land moreorless to the (still warm) top of a recent eruption - I made 4x5"s at all these spots.
Iceland was really lovely, and food is cheaper than in Melbourne. I really want to visit again and explore the north...