If Goal = final rounds have maximum probability of matching the "best" players against each other, then traditional top-vs-bottom seeding is optimal.
If Goal = have equal probability of same degree of difficulty for all entrants, then totally random seeding is optimal.
If Goal = maximize probability of winning for the greatest number of players, then #1 vs #2, #3 vs #4, etc. seeding is optimal.
There's a feeling among many players that the current state of pinball is a lot of "the rich get richer" at many of the larger events. It would be refreshing to do version 3 and see how brave the top guns are when they would have to face each other early on. You could make it double elimination to cut them some slack in that regard.
At HUC, we'd have had round 1 of Raymond vs. Trent, Andrei vs. Karl, me vs. JohnnyPlague and Tim vs. Fred, with round 2 the Raymond/Trent winner vs. Andrei/Karl winner, and me/JP winner vs. Tim/Fred winner, then those two winners in round 3, after which only one of the top 8 would be left in the winners bracket, giving everyone else some hope. Thinking it over, this would have been more exciting in many ways than the seeded version, i.e. a greater sense or urgency for the top seeds to do well right away, and more mystery around who from "down below" would make a deep run in the event. Maybe we should give this version a shot some time in the next year to see how it goes.