Why not using Hexa or even better BASE 36 ([ A-Z0-9] ) to shorten the numbers used as index though the site ?
I also suggest to shorten the name and the values of the parameter passed (to 2 characters whenever it's possible).
and compression wouldn't hurt too, after all(?packed="d22eA5Op2ds78kSv4" could replace all those long parameters)...
/me is just kidding...