1) Have whale
2) Have icelandic horse (#2 on food list)
3) The Northern lights is very temperamental (1 guy tried 7 times - clouds). If it happens, it happens.
4) Reykjavik is a very small city. If your hotel is 1.1 miles away, it's in the suburbs!
5) Don't plan a whole day on the blue lagoon. It's on the way to the airport (15 mins away).
6) Reykjavik cab fare is $120 (45 mins away from airport)