i use robopacers all the time. the main draw for them, i think, is the predictability. you get a group ride at any time you want to start that is roughly the same experience each time. i tend to ride at a time (8:30pm EST weekdays) that isn’t super popular for group rides, so pacers often fill the gap.
i use the pacers to try to ride for longer at paces i am not proficient at. for example, i can ride with yumi for quite some time, but i often try to ride with jacques to see how long i can hang on. note that if you pick a bot at the edge of your ability like this, the dynamic pacing on hills is really nasty – i find i can stay with jacques a lot longer on flatter routes than hillier routes.
i also use maria for zone 2 riding.
it might be cool to have a “bot pack” that rides at slightly different speeds. sort of like the roboRacers mentioned above – they’d be pushing at different effort levels, but maybe come back together once per lap. you could try to stick with the faster ones as long as you can, and then fall back to the easier ones if you get tired or dropped. you could also work together to try to get one of the slower bots caught up to a faster one.
i liked the pacers more when they looked like humans. not sure why. it’s totally irrational. but there it is.