I don't see the problem with what the Panthers did. They announced there was a reserve... they didn't say what it was... if you don't like that, don't bid. I believe I did the same thing with Andre Johnson when I was the Texans GM my first year. Good learning experience... and a lot of fun for mostly everyone. Since the ultimate goal for me at least is to have fun then well there you have it.
I personally don't see anything wrong with auctions. If people don't think its a good format, they wont bid, and the market will work itself out.