- Bigger, better dust bin

- Slightly less dust makes it into the HEPA filter

- Slightly better / cheaper roller design

... and similar details.

A friend gave me their smarter vacuum (which they didn't use), and I hated it:

1) It tried to overthink things and was pretty demanding.

2) It didn't clean as well. My Roomba has a pretty anaemic vacuum, but cleans very well by virtue of going over every place many times in random directions as it bumps along for 30+ minutes. The smart vacuum plotted a course which covered everything once, finished up in record time, and nothing was actually clean.

What's odd is that even now, 2+ decades after launch, so little has improved. What I really want is "cyclone operation," as in any modern dumb vacuum, so most of the dust doesn't make it to the HEPA filter. The design is stupid simple:

- Air comes into a circular container from a hole in the side, so the air spins.

- Suction comes out a hole in the top at a half-way point in the radius of the dust container, while most of the dust wants to stay at the inside or outside

- If you're even more clever, you put the suction at half height, because dust naturally goes to the bottom.

The annoying thing is cleaning or replacing filters.