I personally think the guidelines for a good buy/trade thread should really become RULES for the buy/trade thread.
www.elitefourum.com/t/how-to-make-a-good-buying-thread/12976/1
All the constructive criticism you need can be found in there. Make your post like that if you want it to be successful. These are frequently traded cards with well established values albeit not as frequently traded as complete sets.