Thanks for your replies,
this is a rather complex data structure I have to make accessible and maintainable through an easy to use UI.
I have a change-event-listener at the data-root for some necessary functionality,
so every change, no matter where in the tree caused a re-render of a big part of the data visualization.
This bug became very obvious when I had to update a few hundred helper attributes that show up only in a very deep maintenance dialog, but with every update the whole UI froze for almost 30 sec.
The change-event-listener at the data root is now only responding to the exact attribute it needs to and the problem is solved.
My bad, sorry for making a fuss.