For example, if I have a Panel containing several views, pressing those keys while focusing on the base selects only the Panel; even if the Panel has focus, the views it contains aren't selected.
Yes, or by clicking on the base/activity, press CTRL+ALT and exclude PnlChessBoard and other views external to the panel, keeping selected only the boxes (panels/labels/image views) inside PnlChessBoard
I created a simplified test layout and noticed that CTRL+A ALWAYS and ONLY selects the top-level views, those in the "Activity." In short, it's not recursive.