Queueing As a Role, not a Class.

[SaitoHikari]

It would mess up the matching system. It tries not to pair you up with the same type of DPS for 4 mans and such. If you just made it by role instead of class it would through a wrench in the matching system.

The devs could split DPS into 'melee' and 'ranged' to try to alleviate this.

However, on the other side of the spectrum, I could see people giving others grief over not leveling other classes because they want the other person to switch away from the class they're using.

I think what would be a particularly good quality of life change is something completely different: Allow people to switch classes freely out of combat if someone leaves/is vote kicked and 5 minutes elapse without a replacement. That way instanced content doesn't basically automatically end the moment a tank or healer leaves, assuming someone present has a sufficiently leveled class of those roles.