Supporter Plugin Feature request

wanted: multi tier user access levels, variable price points

We would like to be able to have multiple billing options built into supporter.
example:
$9.95 membership level (0)
$15.95 membership level (1)
etc....

Possible use to determine level would be adding an argument to the is_supporter options like so: is_supporter(#)

is_supporter would default to argument = 0 for backwards compatibility.