Oh hai!~
I have a few suggestions for the event, considering that the Summer event is ending soon (sigh).
The Kraken does not appear every time. Sometimes it may not appear for two events in a row, and not everyone has the opportunity to go to each event. Someone can visit no more than 2 events per day.
The map is quite large and the speed of movement on it is limited. There are also a number of obstacles - crabs, waves, tsunamis. So the Kraken appears in a random place and, if not next to you, it takes time to find it. And not all people are ready to wait until others get to the Kraken. Even if someone asks to wait. Thus, not everyone has time to get to the chest to get their loot, even if they were very close to the Kraken, but they were carried to the shore. Or someone who was on the map from the beginning of the event did not have a chance to reach the Kraken or at least get loot from the chest.
My suggestions:
1) If possible, increase the probability of the Kraken appearing. Or at least explain, please, what needs to be done to make sure it appears.
2) Add a marker for where the Kraken spawns. This will help people find it or the chest faster.
3) Increase the time the chest stays on the map. This will protect against selfish people who don't care if others don't get their loot.
4) Increase the chance of costumes dropping from the chest. During the entire event, only two people (as far as I know, I could be wrong) got costumes.
Why is this a good idea?
Because it will remove frustration and increase people's happiness.
What risks or downsides does it have?
I don't think there are any risks here.