Yeah I thought about returning my Mini 6, which has a good display and no to me visible jelly effect, because of a bit loose buttons, esp power button. But otherwise it is really amazing, no problems. Display almost perfect, can't reproduce jelly, even if it is there. Good contrast display, no touch problems like here. I will keep it and use AC+ of something really happens with the buttons.
The jelly effect might be one thing, not everyone sees it. But the touch issues is definitely a hardware defect, sorry. I hope you get a good one next time or some other time in the future.