If the goal is a better customer service experience, I would go with option 2. Option 2 will answer the call before option 1 or 3 because the call is queued to all 3 skillgroups and as soon as a person is available in any of these skillgroups the call will be presented.
Option 2 will also result in less of your employees doing nothing while there is a call waiting in queue.
The only downsides to option 2 are the reporting and statistics gathering for the skillgroup. I am currently using a queuing system similar to option 2 and I only use call types for reporting purposes.