I took a road trip with the Kia Sorento and Honda needs major improvement in ACC technology. The ACC on the Sorento was human like. I was blown away with their stop and go technology.
ACC for the Honda is good on the highway moving at speed, but as you say it is not great for low speed follow with stop and go. I will have to drive one of the Kia's at some point. My i3 is not as good as Honda for ACC overall, but maybe better for the stop and go as it accelerates quicker.
Put it in Sport Mode or at least turn off Econ and it will accelerate faster in LSF. Maybe not enough for every person behind you, but definitely better.
Honda has too much delay. The Kia was moving forward just like I would do in stop and go traffic. We were stuck in stop and go for one hour due to freeway closure and my wife didn't know I was using ACC. The Kia is also fantastic when other vehicles merge into our lane. The Honda ACC is too slow to recognize merging vehicles making ACC scary in heavy traffic. P.S. ventilated seats and extended thigh support are the new must have. If only they had lane keep assist.