Hi zulu85,
I assume you went through this series already:
https://www.cineversity.com/vidplaytut/a_cinema_4d_primer_for_maya_artists_selecting_objects_and_components
Perhaps another entry for the suggestions option of Maxon? It is a request from Maya users already, but probably that a Shift-Click on the objects is so simple that other suggestions had more priority. Maybe your 1+ will push it higher on the to-do list. I have no idea if this is a patent hold by Autodesk that prevents this option elsewhere.)
As long as the mouse indicator is in the Editor view, there is, so far, I have researched it, no option like this at the moment (I searched mainly for a python script.)
• Typically you can select multiple objects with Shift-Key and click. Besides, the Control-Click on the object will give you the list of objects at the mouse indicators position.
• If you have selected the Parent, you could use the OM> Edit> Select-Children Command (Perhaps apply a short cut for the Command)
• If you have clicked on a single object in the Object Manager, then the up and down arrows work. While holding Shift, you can increase the group; eventually, you have to start from the top to get all.
• If all the objects of a group are on a specific Layer, that Layer can be used to select all objects “wearing” that label.
• Several objects can be selected at once while they are part of a single Selection Object. Whereby these objects can be all over the place or grouped or even mixed.
All the best
