Simple math really. They need to get rid of that 300ms processing timer and process everyone's xyz the instant they are received.
They can lengthen the aoe 'safe period' by 300 ms. That's more realist than having faster servers.

They should also remove the auto-update position that casting does. Just leave it at the normal 0.3. That way being caught casting won't screw you for 0.3 seconds more.