Suggestion: toilets throughout the level?
Right now, if someone joins late, they spawn at the start of the facility. If the rest of the team is already at the end of the facility and the new player dies (say, during a double wave that was just triggered when the new player spawned in), the rest of the team would have to backtrack all the way to revive the player. (But maybe this is intentional and designed to help the new player to get bio-boosters and workbenches etc.)