As a Roblox Developer it is currently too hard to bulk select within a model.
Alt + Ctrl or Alt + Shift works to select within a Model, but you can only select 1 at a time. If we were able to use Alt + Drag you could select many things very quickly.
Example 1:
You’re adding custom siding to a wall, and need to hollow out a section for your window. With Alt + Drag you could do it all in one fell swoop instead of having to select one at a time.