Teambuilder Ranked

Don't know if this is a concept already out there or just me thinking out loud. A problem I see a lot with pre toxicity is someone upset about not getting a role. Now before I get jumped, I know that playing ranked you should have general knowledge of all roles. But as a preventative toxicity measure, what if we could queue and select 1 or even 2 roles (2 to decrease wait times in queues if needed).