[Jords]

My ideas:

1. Stick with normal nominations but every 3 weeks have the whole house do a task, those which complete the task are safe from evictions, those which fail go up.

2. Have a lottery number type machine with the numbers 2,3,4 and the word ALL. For nominations a HM randomly picks a ball and whatever the number is the minimum amount of HMs that have to go up for eviction that week. This may mean being told whos up for nominations after round 1 of nominations and doing a second round. If the ALL ball is selected, all housmates face the public vote.
Other balls could include (for twists or to be put in every 2 weeks): YOU, which means the person doing the lottery goes up plus the minimum of 2 from nominations. And YOU DECIDE, which means the person doing the lottery decides the 2 HMs which go up (not allowed yourself).
There could also be PUBLIC, which means the public vote to nominate that week and the HMs evict on Friday.

3. Same idea as 2. except the number corresponds how many nominations you have to do. If you get the ALL ball, no nominations, all HMs go up.

Possible nomination twist ideas:
The top people who are nominated are actually safe, the rest go up.
Having a week where the hosuemates make a group decision which housemates go up (the most that get agreed to go up - this could cause trouble).
Have the top nominated HM's nominations be the people up for eviction.

Those who do not nominate go up straight away first time. Second time all those who do not nominate the ones not nominating go up with them. Third time kick them out.