Abuse possibility one: With low enough of a punishment that full ranked teams could use it as a lesser penalized dodge. Solution? Disable votekick in fully stacked teams. There should be no reason to kick if youre a 5 man premade. You should know full well that that dude is a tool BEFORE you start playing with him like that.
Abuse possibility two: In normal draft 4 players gang up and just keep kicking people for... Who knows... People are dumb. Disable this feature in normal draft.
Abuse possibility three: 2 man duos go around kicking games repeatedly. Solution? 3 is more than 2. 2 guys start spazzing out demanding someone be kicked, at least the other 3 should be smart enough to weigh in properly.
Abuse possibility four, and this is the only one I really see as being troublesome: Someone picks a champ that people dont like and they instakick him. A friend of mine likes playing Heimer with promote. They took Morde mid, which this setup completely DESTROYS Morde so my friend gladly took his favorite champ and spells. Our team started complaining pretty bad that he would make such a pick in a ranked game. In this situation he may get kicked by a team having a rage fit over his choice. Solution? Sadly this doesn't have one other than smart or understanding teams. We managed to tell them he knew what he was doing and we won that game fairly easily and they apologized for their earlier lack of faith. Sometimes you just will not get teams like this, though, but I pose the question of why would you want to play with them anyway if they are too stubborn to listen? Bodes poorly for teamwork if they're already that upset before the game even starts.
Both sides weighed? At the very LEAST it's worth a test run. It's not like the current system isn't easily abused. Don't like the team comp? Grab Ashe with smite and clairvoyance, demand that you are jungling and going AP tank, and it's risky, but you're so freaking stoned right now and you play better high. Congratulations, you just wasted a half hour of someones time and are free to immediately go do it again.
This system will only work in ranked because the max amount of players that can que together is 2, and it requires 4 to kick some one. As I do recall 4>2 so please read the OP before writing your disrotation on a forum post you didnt fully understand.