With being in an 8 team conference before, I've seen some strange things happen when it comes to seeding for the play-offs. I recall one instance where 3 teams were tied for 2nd place. It literally came down to a coin toss to determine the full order. Imagine having your seed determined by the flip of a coin?! With this being said, I would think that if there were a tie in seeding (especially a tie for 4th place), that would make that team an instant at-large instead of a 'play in' game? Or stranger yet, imagine a ranked team getting bumped out of AQ status after the tie-breaker scenario's. So perhaps a ranked team that did not AQ would be an instant at-large instead of a 'play in' as well?
With AQ's the play-off system will always be flawed. We all recognize regions that are strong soccer (or any other sport) regions and others that are weak. There are often teams that AQ which, truthfully, don't deserve post-season play. Then there are teams that do deserve to be there but didn't make the cut because they play in a strong region. I don't foresee an easy fix to the playoff system, however the one presented makes the most sense and seems to be equitable to all.