Right to Stay Challenge

Like on the show Endurance, make this season's competitors EARN their spot by competing in a challenge before being assigned to a tribe. It could any type of challenge really, but usually it's an endurance one (ex. Posting in thread every hour for 24 hours. People who post least get eliminated). If you do this twist, I would say cast like 25 people and only 20 make it onto a tribe.

Everyone must say how they vote
at tribal council

so basically no anonymous voting

Anarchy

New tribes every day

Well Redemption Island with a twist

at redemption island their is a idol

if you lose the duel at redemption island you can play the idol and the person that won will go home instead

Redemption island

I have a few twist
Saboteur-One person on the Island can trade information to the other tribe. And basically tries to sabatage their tribe. If they make it to a certain part in the game. They are given an immunity idol or another reward. 

or-

Tribe Swap- Every 6 days has a tribe swap.

or-

Twin Twist- There are two twins assigned to eachother. They both are on one tribe. The goal is to get their twin out. If there twin gets out then they are safe until the merge. Each tribe will have a twin. If they don't succeed nothing happens.

2 tribes swap into 4 tribes and a new idol is placed at every camp

Another twist:

Everyone gets a pice to an idol
You can mail the host if you want to give your piece to someone or you want to give a fake piece to someone
The host then tells the person they got a piece for an idol but they don't tell if it's fake or really
You need 3 or 2 pieces (hosts choice) to have a real idol
But you never know one of those pieces could be fake
Once you are out of the game you have to give your piece to someone left in the game

Assassins- You randomly generate a list of all contestants. That order is the assassin order. Each person is given the name of the person that is their target so 1 goes after 2. 2 targets 3, so on until 16 completes the list and targets 1. If your target is voted out you get immunity at the next tribal council. Your new target becomes the target of the person eliminated. So if 2 gets voted out #1's new target is #3. The twist ends at final 5. This is a twist I have thought about a long time and would love to see get tried out.

Here's a Twist:
The Good, the Bad, and Ugly Idols

3 idols are hidden at different camps.

1 idol will negate all votes against you: the Good

One idol you play will give you 3 votes FOR you when you play it: the Bad

One idol, you will play for someone and they won't vote at Tribal council: the Ugly

Kind of like what Danielm said except a more committed twist.

The Pangaea twist! Everyone is put on one tribe from beginning to end. So basically the whole game is a merge which will give it more of a Stars vibe than most other twists as voting blocks will be used rather than a clear alliance slaying from start to finish. It'll take a lot more strategy to win the game with 20 people on one tribe rather than 6.

The winning tribe get to vote out a player of the losing tribe. Would only work if there are two tribes.

Independent Tribes

2 Tries of 10 that act like separate independent merged tribes. With separate individual separate immunities, idols, and separate tribal councils. Once both tribes are down to two  people, the final tribal council begins where 1 sole survivor will be crowned

The un-merge. The tribes merge at a higher number maybe 15 and then at say 10 they unmerge for a couple of rounds

For the record, I didnt read anyone else Twist Ideas. So If i repeat then great minds lmao
Twist 1:

This season, instead of the losing tribe voting off 1 of their own. That decision is left to the winning tribe.

Twist 2:

Who plays this Idol becomes the sole vote for that tribal council, all other player's vote will simply be cancelled.