The double-elimination format seems to have the most traction. It has its problems, especially on the final day, but it does guarantee that every match is an important match for the teams involved.
To help CCP in this regard, I've not only drawn up a large bracket sheet, I've also scheduled every match across the eight day tournament schedule.
The following images are quite large. (Click here to download.)
Either stick with a format that will contain pointless matches, or move to a format that is going to be setup overload for some teams on the final day. Doesn't seem to be any middle ground.