It is already discussed here multiple times.
Just a recent example. You might wanna try the search engine first, before starting a new thread about the same subject. I think threads like will pop up weekly.
I prefer a different solution, that is time penalties for quitters. That makes much more sense. If you just want to play one map only, then you go to the lobby and host your own games with your preferred settings. It make no sense to annoy people by quitting, because the quitter dont like the rules of ranked.