That time is literally pointless because it starts counting down when the last person loads in anyway. So why not actually be able to do something with that time instead of literally going to take a piss or whatever? Maybe opening chat up for that time period to either talk some strategy or to just kill time, with a more extreme option being changing around team composition while having free chat, while keeping the one job per team restriction. That would also give a good idea of what jobs people consider strong and where to take job balancing more consistently.

Just some ideas from a guy bored by standing still or jumping around for half a minute