I see this being driver by what you want to store. The items to be store can change the optimum design. For maximum use of space I agree that abandoning the under the landing area makes sense. I would make deep cabinets with pullouts on full extension glides. these allow you to open the door and pull the entire tray out for easy access to everything including those items that are in the rear.

This method works great in kitchens and bathrooms where odd shapes cost valuable storage space. I have also doubled available space in closets using these. For visual interest you could make deep, doored cabinets with pullouts as lowers using the post as a dividing area, visually and literally. Then for uppers you could use shallower shelves if that suits your taste.

Glenn's-Pullouts.jpgJan's Pullouts 004.jpgJan's Pullouts 008.jpg