My ideal lawn mower is a robot. Rumba vacuums are not robots, but dumb substandard vacuums with mindless wondering, bumping into walls and going some place else. This does not work outdoors, where the problem is different. Current offering are the mindless kind needing complex electric guidance fences. Terrible and overpriced.
To start make a really powerful lawn mower, with two 60v batteries. Make it for the normal mowing application with powered wheels and handle for user guidance with controls. However make the front wheels pivot and the two rear wheels independently guided. And allow the handles and controls to be temporally removed.
Then add a robot feature. Not a separate compromised product. Current middle school students can program robots made to compete with other robots, avoid obstacles, perform complex tasks, and respond to adverse environment actually intended to defeat the other robot. Drones fly in three dimensions at 25 miles per hour, avoid objects, identify a person and follow them. If 12 years can do this you can make a robot that mows the lawn as an add on feature.
Then the user can ask the robot to watch him mow the lawn, and remember the user mowing the lawn, and the robot can do that over and over again. Nothing pleases an OCD more than being imitated for the value he creates.
Control this with WiFi control like a Nest temperature control. Make schedules, monitor the weather for rain and dew point. Heck I can have the weather app tell me the ideal time for a bike ride, why not the mower the ideal time to mow the yard.
Adding surveillance video (camera on board), can be for other vendors, but it is a safety feature many will want.
If you understand what you are doing, the proof would be that a Homeowners Associations could send the mower out to mow 50 parking strips on three streets (for example).
Adopt an industry standard for all this.
It is beyond the scope of this request but you can imagine a single robotic lawn mower doing all the lawns in the neighborhood. Memory and computing capacity is not a limitation today, only your vision.