Tilemap brush list too long?

I guess you could just have one Prefab Brush and change the prefab you want to paint with in the Object Selector under the Prefabs list instead? This should cut down the Brush menu size.

In the future, the GameObject Brush and the Tile Palette will be updated so you can pick these up from the Tile Palette instead.

 

Yes, it has! You will need to do a little bit of setup to get to it for now:

• Install 2020.1 beta from https://unity3d.com/beta/2020.1b
  
• Ensure your project has the 2D Tilemap Editor package
• Install the 2D Tilemap Extras package from https://github.com/Unity-Technologies/2d-extras/tree/package_2020.1
  • Requires git to be installed on your computer
  • Enter the following in Package Manager
    
    https://github.com/Unity-Technologies/2d-extras.git#package_2020.1
    or
  • Add the following line to your Packages/manifest.json file in your Unity Project under the dependencies section:
    "com.unity.2d.tilemap.extras": "https://github.com/Unity-Technologies/2d-extras.git#package_2020.1"
  • If you do not have git installed on your computer, you can download or clone this repository into your project in the folder Packages/com.unity.2d.tilemap.extras
• Select the GameObject Brush under the Tile Palette to use

 

For 2020.1, you should be using #package. Alternatively, you can install the Tilemap Extras package using the Unity Package Manager as well.