Hmm, I was thinking something more along the lines of:

When kicked out, Joining an existing instance will not pick up an instance one was kicked from. (It can be the same dungeon, just not the same group).
Vote kicks within the past hour accumulate an increasing penalty. 1st vote kick = no penalty, 2nd vote kick = 1 min wait, 3rd vote kick = 5 min wait, etc...

This should be enough to protect people from disruptive players while reducing the possibility of abuse.