In what ways? The Roomba J7 I'm using is pretty amazing at what it does; the only thing I'd appreciate would be a remote control for some manual cleaning. The automatic stuff is pretty great.
For starters, the best Roborock supports improved mopping, including a dock with self-emptying container, self-cleaning mop and proper refills. Together with noticably better obstacle avoidance algorithm.
The new Xiaomi versions now even sport extendible arms to reach corners fully.
On mops: The newest Dreame model can actually disconnect the mops and leave them in the dock, so because of the relationship through Xiaomi people seem to expect that to come soon to Roborock as well.