Tuesday is also Shavuot, one of the main pilgrimage festivals in Israel. I don't know the first thing about it, but it's an important holiday, and I was already scheduled to go to Tel Aviv on Wednesday, so I figured I might as well go a little early and see what all the fuss is about.
One thing I know about Shavuot is that it's supposed to be better in Jerusalem than Tel Aviv. That's easy enough to believe. Tel Aviv is a better party town, but if you're doing a religious festival, Jerusalem is the place. Getting from one city to the other is very easy, so I don't anticipate any scheduling conflicts.
The Dragon Boat Festival is pretty important in China, but I've seen that several times. Coincidentally, it's also a holiday I've missed a few times because I was out of the country. That's probably because it's always at the beginning of summer. I took a cruise a few years ago and we happened to dock in Hong Kong during the Dragon Boat Festival. That was pretty interesting for me because I was on a cruise ship in my own city, and the views of the dragon boat races from the top deck were incredible.