Each week, the person who survives eviction is able to automatically choose one of the housemates that will be up for eviction the following week.
So the house all nominate like usual, except the eviction survivor.
Then the housemate with most votes is up for eviction, plus the housemate chosen by eviction survivor.

Doing this means the housemate up for eviction gets revenge and also it would stop a large group picking off a smaller group one by one all the way to the final, which could happen in this series.

I think something similar happens in the Indian BB.
Bear with me, 'cos the facts/details might be a bit sketchy.

I think that the eliminated housemate chooses the next person up for nomination or is able to contribute to the voting.
They also have a weekly.. voted for.. leader who is charge of the shopping and divvying up household chores, which the rest of the housemates have to adhere to.

They should do reverse noms one week . Whoever gets the least nominations go up for eviction . Not every week , just the one time.

or the 2 housemates with most votes get to choose 2 other housemates to take their place

Yeah that would be pretty good

Also any twist would be fair at this point seen as they can take away someone's voting rights for not doing anything wrong.

Didn't they do this with CBB last year - or was it the evicted HM got to chose one?