if we had bid agent please no smart ones, just make then like ebay(or at least the old ebay i know).
If you bid, the praise raise to the minimum price you can buy it, if someone new bid the dude with the higher price get it to the amount of the lower bid + X. But mixing systems up, and making automated bid wars, who occur through different timings would be annoying for me. And it is different for a human to bid against a maschine, who never forget to raise the price etc.
And here is the question, are bid wars fun or just annoying?