I am currently redesigning my kitchen in a 1930's Midwestern USA house. The kitchen has a decent floor area but the floor plan is oddly restrictive.
My space next to the sink is such that I can either have a standard 24" dishwasher next to the sink and a slightly weird cabinet adjacent to it, or I could have an 18 inch dishwasher at 45 degrees flanked by two small but reasonably sized cabinet doors (or drawers), although the 45 degree plan would dictate a somewhat shallow custom counter depth on the flanks (like 18-20 inches).
I think I would be more proud of the accomplishment of building the angled design, and I think the ergonomics would be optimal.
But I'm not sure about the smaller dishwasher. I have never used a smaller one. It seems like it would be enough for my small family and still plenty helpful for gatherings.
The apartment we bought came with an old 18” dishwasher.
We run it daily with two adults and it works great. Even though you need to run it more often, it’s takes less time to empty than a full size.
For our current layout it makes a lot of sense but would want a full size if the family grows.
If I was single I would prefer the smaller format. I find it kinda nasty to have my dirty dishes standing for many days.