Riot should look at it this way
Is it fun to have your role taken by another player - No
Is it fun to have to wait 30 mins - Hours to play another game because someone trolled and you dodged - No
Then why does this system remain in place? What is the philosophy behind this system?
You don't have to set the meta in stone to have a role queuing system, separate it into two queues.
1 - Queue for freeform meta meaning the team won't follow the conventional meta
2 - Queue for meta, 1 Bruiser Top, 1 AP mid, 1 Jungle, 1 Adc and 1 Support