Of course you can - make it like in football. First of all, don't gather the 7th, 8th and 9th in the world ranglist in one group, split the streams according ranglist with no host advantage, make the matches from one group in the same time, not in the same hall, first from one group against second, and it will be OK. There are never problems in football in that way, I mean, one mistake in the group is not enough to stop you from semifinals, no calculations possible, no gathering of all strong teams in one stream.
Agree with you, it's the best solution, but FIVB and CEV don't think the same