How to show detailed value labels in a Tableau treemap?

I have the following travel data showing the counts of trips that specific users have done to specific destinations.

My aim is to draw a treemap that shows all the destinations that each user has travelled to, colour coding and size coding the treemap by the number of destinations for each traveler. Right now I have something like this but the issue with this viz is that the smaller boxes don't show all their text as it doesn't fit properly.

I know I can remove the Destination pill from the Labels Marks to stop the treemap being broken down into individual destination boxes too (see below). But in this case and for each of the user rectangles, how can I show a list of all the destinations that a traveler has gone to?

Assuming that you need to visualize the destination list regardless the dimension of each traveler "square" in the treemap, you may want to give a try to Viz in tooltip.

Essentially you can create a worksheet containing the destination list, and then using it "inside" the tooltip section of your treemap.

Let's assume for a moment that your treemap is the following barchart, you can get something like this (based on superstore):

Doing so, just hovering on your travelers (category from superstore) you coud get their destination details (subcategory from superstore).

You can find here some additional information from Tableau official documentation.