2v8 - Anti slugging measure
Since people are people, there are those who will try to slug the entire team of 8 (I've just witnesses such a match on a stream), and it creates an awful uninteractive gameplay. Slugging in normal game mode has its pupose, but not in here. You don't have to fear flashlight/bang/pallet saves, hook sabos, DS, FTP, etc. You can immediately cage, always.
The only exception is if you down someone and someone else is immediately there, and you want to take the opportunity to down them quickly (if possible).
My suggestion is give everyone unlimited basekit Unbreakable, but make the recovery faster. This will never make survivors OP, it will only prevent killer teams that have the intention to slug everyone for their own personal thrill, from doing that.