Space creation flow makes poor use of space

### Your use case

#### What would you like to do?
Quickly and effectively browse rooms that I am a member of

#### Why would you like to do it?
To set up a private space for organising my rooms

#### How would you like to achieve it?
By having "what do you want to organise?" view make good use of the available space.

### Have you considered any alternatives?

_No response_

### Additional context


At the moment, most of the screen is unused, while I am in dozens of rooms which I have to browse through a small scrollable area. The area could potentially expand up to window height before it becomes scrollable so that I can see more rooms at the same time.