[Jason.]

I'd love the staircase to be in a separate room, like that of BB6-BB10.
More like BB6-BB8, though as I wasn't keen on the Diary room being under the stairs in BB9 and BB10.
There was just something so atmospheric about the evictee standing at the top of the stairs, waiting for the doors to slide open, and hearing the housemates muffled goodbyes, as the doors shut.
Though for that to work, they need to scrap the countdown, and actually show the evictee right before the door opens.
This also makes secret evictions, and housemates entrances good too.
Like Aisleyne's iconic HND moment, when the crowd reaction happened, and part of the wall opened, which led to the secret house.
And Big Brother saying, "Housemates MUST to shut the front doors, immediately".

I'd also love for an outdoor lounge, in a separate room again. Like BB6 and BB10 had.
I used to love evictions back in 2005, when the evictee would say their goodbyes in the lounge, and make their way through the main house alone, whilst the iconic and suspenseful eviction background music would play.

It was also great for nominations and announcements.

The Diary room must be downstairs again.