Assume the O's decide to trade for a quality SP. They send one key guy and other lesser pieces. In each case the lesser pieces are the same no matter which of the three headliners you send out. In other words the opposing GM will do the trade if you offer them any one of the three big names.
So which do you choose:
1. Coby Mayo
2. Heston Kjerstad
3. Jackson Holliday
4. None. I wouldn't trade any of those guys.
Try not to get hung up on who the other pieces are or who the return starting pitcher would be. Just for sake of discussion assume you view the return as getting good value. Simply put which of these guys would you think has the least long term benefit to the O's.