Did Julia’s house layout never make any sense

[TMC]

The living room is huge and cavernous and there’s a full kitchen in it, but no table and chairs in the vicinity. And why was Julia’s bedroom door on the same side of the front entrance?

[hch]

You are absolutely right—the layout of Sugarbaker & Associates was a masterpiece of "sitcom physics" that bore no resemblance to the real Villa Marre in Little Rock, Arkansas, which served as the show's exterior.
Here is why the Designing Women set never actually made sense:

The "Cavernous" Kitchen/Living Hybrid: In the show, the kitchen was essentially an open alcove within the massive main room. While Julia’s desk and the design workspace were the focus, the kitchen sat tucked in the back without a dining table because the real-life house interior actually has separate, formal rooms. On the soundstage, a dining table would have blocked camera sightlines and cluttered the "catwalk" space where the women did their fast-paced walking and talking.

The Impossible Bedroom Door: Julia’s bedroom door was famously located just to the left of the front entrance. In a real Victorian home like the Villa Marre, that space would likely be a foyer or a parlor, not a master bedroom. This placement was a technical necessity for the actors to make dramatic "grand entrances" or exits directly into the main action without needing a hallway set.

The Mismatched Entrances: Fans have often noted that the exterior front door of the real house is a double door, while the interior set used a single door. Additionally, the porch would disappear or change size depending on whether the scene required the ladies to sit on it or just walk through it.

The Vanishing Upstairs: Despite having a prominent staircase, almost all "private" moments happened in the downstairs bedrooms (Julia’s or the guest room/office), making the second floor largely a decorative backdrop.