As I understood it, Harry's revulsion wasn't against the need for a sacrifice but against Dumbledore's fear, Harry would consider the cost of a sacrifice as comparately low. Thinking about ways to lower that cost would not have convinced Dumbledore that Harry took that cost serious the way rejecting the thought outright might have.
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
From previous post: