I would personally prefer an election with simple majority, and a second round between the two candidates that had the most votes in the first round if no one gets more than 50% (ie French presidential election system, among others). This is easy to understand and would give, I think, more legitimacy to the elected candidate, knowing he/she is the first choice of more than 50% of the voters, rather than being the second choice of 70%.
This objection makes no sense to me. If your first choice candidate isn't in the the runoff, you can't vote for him or her, so you vote for whichever of the remaining candidates you like the best, which, in a reasonable world, would be whichever of them would have ranked higher on your STV ballot. In effect, it's just a slower and less fair way to do the same thing. Note that in STV, if one candidate gets 50% of the votes, the election is over, and the transferrals only happen so long as nobody has a majority. If as people seem to be saying, our electorate is so innumerate that they cannot ask themselves "who would I vote for if my preferred candidate weren't running?" then I guess we should do something else. But it is a sad commentary on the voters. R's, John