4. Water ballast bags are freakin' amazing. The Butlers were in a Switlick 4-man (which, again, was not quite big enough for 2 to be comfortable). The ballast bags were rectangular (not triangular) with chain at the bottom of each bag. They went through some huge storms with breaking seas up to 25' and never rolled once - WITHOUT the sea anchor in the water.
It should be noted, that most liferaft companies calculate the weight of the people in the raft(its capacity) as part of the ballast. Hence, oversizing a liferaft, for space reasons, will increase its tendency to capsize.
However, the lack of persons in the raft can easily be offset by substituting each person with 4 cases of beer. Just don't drink the ballast....