Well, this would also give big players an advantage. They can afford "big aircrafts". New Players which usually start with smaller aircrafts (Dash, CRJ, EMB or small Boeings and Airbus) would loose their slots on the big airport. Where is your problem with the actual system? First come, first serve. This it’s fair. No big regulations. Everyone understand it. There are only a few players who use dumb tactics and use LET and Co. to blocking slots. However, there is no need to change the actual system. At some point of the game, the slots will be a rare good, no matter which system you have. Even with your system, there will be airlines who will have up to 5.000 departures … maybe with 767s on domestic routes.