For Vote Kick, I would suggest these rules:
1) First-timers to any dungeon (players who have not completed it yet) cannot be kicked unless they are AFK/disconnected.
2) No kicks during combat, no kicks directly after a boss is downed & loot is being rolled on, and no kicks after final boss has been defeated. Each player can vote toward limited kicks per day, and a dungeon party has a cooldown on successive kicks.
3) No kicking a player in the first few minutes of them entering a dungeon, for any reason. I'm tempted to include something about kicking just before the final boss, though I'm not sure about the particulars.
4) In a Light Party, you need 3 out of 4 players to pass a vote to Kick. In a Full Party, you need either 6 or 7 out of 8 (I'm not sure of exact number in this case, perhaps the requirement could fluctuate based on circumstances).
5) There should probably be limits on the amount of kicks a player can vote in per day, or perhaps a cooldown on kicking for any particular group. This inhibits repeated kicks, and kicks for petty/minor reasons.
6) Replacements for kicked players must be drawn from the random Duty Finder pool. Manual invites to specific characters are only possible if someone leaves voluntarily, or was AFK/disconnected.
7) A player who is kicked while AFK or disconnected will count as having abandoned the group, and will suffer the penalty for leaving. Apologies to those of us who get legitimately disconnected against their will, but this is necessary to deter the players who intentionally "disconnect" rather than leave. AFK or disconnected characters will automatically be removed from the party after a given time, if not kicked.
8) The penalty for abandoning a DF group increases with each group you abandon per day. Penalty for leaving a group that includes a first-timer is also increased.
9) Someone told me that in WoW, they implemented a system where players who were manually grouped together before entering DF were collectively counted as one "vote." Sounds good to me, though I haven't fully thought through possible downfalls.
I really like this, though I'm not sure how effective it would be with cutscenes that are advanced via text boxes, at least as far as it being "anonymous." The player who is still reading is obviously the one who didn't skip. :-P
Maybe the text doesn't advance until all players approve?
Oh, please. As it is, a single player can decide to ruin an entire run for a party of 4 or 8, and completely waste their time, all while taunting them and daring them to take the penalty for leaving. I'd say that a far more effective way to grief than 3/4 or 7/8 players coming to a consensus to remove 1 player for being a problem. As I and other people have pointed out, there are myriad ways to build in safeguards that minimize abuse and put a muzzle on FCs like yours.
As far as the MVP points system, I'm not aware of any way to abuse it yet. Most criticisms I've heard of it are from people who haven't read up on it, and refer to flaws that don't exist. There are no "down votes." You can't award MVP points to anyone you manually grouped with before queuing -- it's only for randoms. Points are awarded anonymously, after the dungeon is completed. There is no way to make any sort of deals/threats with regards to how points are allocated. You can't "sell" a run for MVP points, or try to coerce anyone into awarding points one way or the other. You literally get them for being a good team player in Duty Finder.
Derp. Okay, so that's one potential shortcoming, even if it isn't really an "abuse". As a DPS, I have also thought about this, but it seems I forgot. Hard to say, we could still end up getting points for having a good attitude, playing well if others aren't, providing advice/strats on bosses, etc. Or maybe this is an incentive to try tanking/healing for a while? Whatever the case, I'd still rather this feature be in the game than not.