Its not about query performance on cluster rather it is about editing a databricks notebook. it takes longer to edit a cell and most of the time it shows a popup of the browser that the databricks notebook is not responding. Hope it make sense

Did you ever figure this out? The best I can figure it breaking up into more cells or separate notebooks....

The notebook editor has been sluggish for me regardless of splitting up between cells and the language in use. Very frustrating.

I ended up just breaking up that notebook and using the %run command to run them at the same time

A DE I work with was saying to keep cells under 1K lines and notebooks under 10K I believe so I'm just splitting them up more now.