I'd go for Seasons. I have meny worlds so it's a great effect from the changing seasons in most of them, but also I think most of the weather changes came wity this pack. Most worlds have their typical seasons and weather pattern. Like heat waves, rain, storms and temperatures. There'sa a lot more to it than just a sunny day or snow or rain. Nature develops gradually, not overnight.
With Island you would get Summer of course, but I'm not sure how variedtheSummer would be without Seasons. If you prefer all days to be sunny, maybe IL would be best for you now.
