Ksucats, we bought the Assigned Seating because of traveling with kids. I don't like extras either, but we didn't want a hassle over sitting with the kids since flying is something special to them and it is great to be able to share that. We did not pay the additional cost of Priority Boarding and that worked out just fine. Those who paid for both board in the first group, next are those who only paid for Assigned Seating, and the third group is general boarding.
The savvy seemed to have selected assigned seats in the back because the back rows are called first and that gives them first crack at the bin space.