Please reintroduce the full vertical size of select-panels (e.g. symbols, styles etc.).
Now, with the restrained height of the panel, when using a large library it is necessary to scroll and scroll and scroll.
I see no usability reason for that new behaviour.
In the meantime, you can use the Command Bar to swap symbols, styles, etc. For that, you can ⌥-click the control on the inspector. There’s a setting to always use the Command Bar for this without requiring the modifier, in Settings > General.