I have over 1000 custom wins, mostly from classic ARAM, and I miss this functionality... I still have a spreadsheet of 207 names of dodgers.
For the original question, I honestly wouldn't mind seeing the penalty increased to an hour or something. But I don't think that will do much to deter dodging, because many people have developed a few ARAM accounts they could switch to. But for someone like me, who does OCCASIONALLY dodge (there are 3 champions I REFUSE to play, because I am just SO BAD with them that I WILL be flamed through the entire match, and that is not fun for anybody,) and doesn't use alts to play ARAM, I would gladly wait longer than 15 minutes as punishment. Or just not dodge if I don't have an hour to wait. I realize this behavior ruins the nature of the game, and even if I think my reasons are justified, they really aren't and it's not fair to anyone else.