I also see the advantage of having no quorum at all. There will be quite a few proposals, which should be non-controversial but won’t be able to reach quorum because they are not interesting enough for all GNO holders.
The Balancer GNO pools are probably a good example of a proposal, which will probably receive no NO votes but won’t reach quorum because few GNO holders will care: Should GnosisDAO allow to use GNO locked in balancer pools for voting in snapshot proposals?.
None the less I think having no quorum at all is not a good step at this early stage of the DAO but should be considered at some point.