I wouldn't really consider the Tetons in the Midwest, they are part of the Rocky mountains. Same with Glacier.

This map seems to capture how I think of the larger regions in the USA

https://www.touropia.com/regions-of-the-united-states/

Probably would divide Socal from Norcal.

Also, there is a distinct inter-mountain west between the Rockies and the Sierra/Cascades. Utah isn't really in the Southwest and Eastern WA/OR isn't really in the PNW but close enough.