It is very clumsy to find a block in the list of names. Sometimes a workfile might contain hundreds of blocks some of them slightly different.
Instead of a drop-down list or a list of names please add a resizable window with previews for each block together with the name of that block below. In this way users can compare blocks and choose the right one more easy. Would be good to choose the size of the previews - small medium-large icons and to be able to just drag-and-drop a block into the scene.
It could look somehow similar to the library panel but for the blocks found in the scene.
Please take this into consideration!