What we really need is a better reporting system.
The last game me and my friend were in, we had a blitz feeding, spamming and harassing. He was feeding by constantly diving into unwinnable 2-5v1 situations when the rest of the team either backed out or died. He was constantly spamming the surrender vote just because he was doing poorly. And he was constantly harassing our ADC for "getting me killed".
Our match lasted over an hour and somehow we won with 2 aspects of drags and 2 barons (we almost lost at the 45 min mark.) and it didnt help with no one grouping until 20 minutes before we won. And both me and my friend were telling the blitz to shut the hell up cuz of his incessant whining.
At the end of it all both me and my friend reported him. But the problem was, he did multiple things during the game worth reporting and there is not option that ties all that together. I know there is an "additional comments" part but considering the topic of which you report them for is for one area and you would be talking about that area along with others, its just stupid.
That is why i want a simple report option of "being a dick" and THEN explain why you think that teammate is acting that way.