Are you using the official Gladys 4 or the zigbee2mqtt built branch? It’s unfinished because you’re using an unfinished branch I think 
The goal of the « device in rooms » box is to look like this:
Indeed, what you present is not clear, it will be changed before being integrated into master
I put my answer on the zigbee2mqtt topic here:
https://community.gladysassistant.com/t/tutoriel-zigbee2mqtt/5097/123?u=pierre-gilles
For the battery display on the dashboard, it’s a debate we have every time 
I put my opinion here: the battery, as long as the battery is good, the user doesn’t care to see it on the dashboard, it’s information without added value. The only use of having feedback on the battery is when the battery is low. There, the user should receive a notification telling them « warning, battery below X% on sensor XX in the kitchen ».
For the story of having a display of devices « grouped », I agree that it would be great!
We talked about it at length this summer in another topic, I invite you to read the debate we had:
For now, no design has really appealed to me, but I’m sure we can come up with something beautiful!
Small remark, if you have feedback on work still in development, do it on the topic of the branch concerned, or on the PR, it’s more practical