I'm wondering if there's a better way to do this. The method I've developed works really well, but I feel like it could be simplified.

My goal is to get the centroid and/or bbox for a group of points or polys. Usually I group the points/polys and use a delete node off to the side to delete non-selected, isolating the group. Then I use a transform node with the centroid/bbox expression on the pivot point to reference the delete node.

Sample project is attached.

It works, but I feel like the whole thing could be streamlined.

There is $GCX $GCY $GCZ referring to the centroid of the input group. Have a look at “Locals” in the documentation of the transform node.