The role changing pill was part of the possible 'gambling reward' from blue Dragon's treasure box right? We don't have the IM here yet so we don't know what will be included and what will not. The only other thing we do have is being able to change role before FD12 at your clan.
The RTD quests were drastically reduced and with the new navigation system, you are literally able to teleport to and from each objective in RTD so even if you don't like one specific role, making a new one would literally take less than half an hour.