A while ago I rented a regular car and what bugged me was all the additional vibration associated with parts grinding and rolling against each other.
Also at least once I almost went "woah, horsie" as the car lunged forward because I tapped the accelerator a moment after it shifted to a lower gear without me noticing.
It used to be even worse. I had an opportunity to drive a 2005 BMW 7 series in a city where the speed limit was 30km/h. Unfortunately the gearbox was from a time way before traffic calming etc. went mainstream, so it couldn't decide which gear to pick. I ended up switching to manual gear selection mode.