In reference to the Trekking to the Everest Base Camp that I did a few years ago in Nepal, I periodically receive emails asking for all kinds of details about it. People need to control well how many days they will need to do the trek beforehand, what is the technical level of the trek and what material is necessary to take from home among other things.
It is difficult to say the best time to travel to Iceland, as it depends on many factors. What are you interested in seeing, the budget, the weather, the comfort, etc. We already told you that there is no perfect season, we went in summer...
For those who are going to spend 4 or 5 days in New York. We are going to give you a series of ideas, advice, and recommendations. Try to see the main sites of the Big Apple in such a short time.