I put all things in masters to let texts from data merge being of different format before the merge.
In case of change in the text (rebalancing the game, mistakes …), I just update the data source in the data merge panel and generate again.
I found it less time consuming than make change detached afterward. Plus, detaching break the sync with the master. I worked as you mentioned on one project few years ago and have been forced to reset the whole document when the client decided to update to a V2 the year latter 😅
Now I put the whole thing on master, it works better with the workflow of game designers I am working with.
(Unfortunately, when I start to design things, clients are still working on content)