The 4 stats shown at the bottom, Ability Power, Attack Damage, Move Speed and Armor should be able to be changed to other stats values.
For example playing as a hero like Master Yi the Ability Power stat isnt as valuable as Attack Speed or Critical Strike chance.
Perhaps on the primary stats window (the one that opens when you click your heroes portrait at the bottom left) you could check 4 boxes you wish and have those stats displayed at the bottom middle?
© 2013 Riot Games, Inc. All rights reserved. Riot Games, League of Legends and PvP.net are trademarks, services marks, or registered trademarks of Riot Games, Inc.