So - though I still don't think the question was tackled perfectly by church leaders, I'll say Question #3 has been answered.
The question is: "Why should a very poor man with lots of debt have to pay tithing to a very wealthy church?"
Though I don't think the leaders directly answered the question in its entirety, they did, however, more or less answer the question.
Yesterday one of the apostles answered, and today President Thomas S Monson answered, that we pay tithing in order to gain blessings, and in order to be obedient, using the example of a very poor man who paid anyway.
I would just like to add a comment about the one quote from the scriptures that says it is better to OBEY than to SACRIFICE. It IS better to Obey than to Sacrifice. Here's my example:
Just days before General Conference in the past week, I made a bad decision. I don't normally make bad decisions like this, but if I had obeyed the gospel I would not have made the mistake. Anyway, my conscience was racked with guilt after I had sinned, and I decided that I would "atone" for my own sin by, more or less, sacrificing 5 times the amount that I had sinned with.
It is, indeed, better to obey than to sacrifice. If I had obeyed, there never would have been a problem, but as I had sinned and I wanted to clean my slate, I, more or less, gave a costly sacrifice of my substance to put me back in God's good graces. And yes, after I made the sacrifice my guilt left and I felt forgiven, but none of that costly sacrifice would have been necessary if I had just obeyed in the first place.
OK, so, 3 questions have been answered, one of them only partially answered but yet answered anyway, a fourth question is sort-of-kind-of-answered if I understood properly, and one remaining question hasn't really been touched. OK, it's possible it was touched, but I'm not getting the explanation necessary to actually answer the question.