Typically, no that's not most optimal. But you can Make Hollow then adjust it. but I'm not sure what you mean by "a lot of grid brushes." If you Make Hollow a cube, you should only get 6 brushes.
Use the cordon tool, anyway your map can't be optimized. You can use the hollowing tool, but imo you can put this tool in the same class as the carve tool (i.e don't use it), vertex/clipping tools ftw.
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