This is the one I use, I think. The hak-less version. It does require manually altering the stats for subraces, and creative visualization for the amia classes. But other then that it does a pretty good job for easily hammering out the basics, and limited testing. It has a leveler, some gear (plus a gear creator), and a few other things that make it easier then just a blank mod.
In addition to what Amarice posted, I alter subrace abilities this way: start with a basic human, type 'DubugMode 1' into the command line, then 'ModSTR 2' or 'ModDEX -2' or whatever else is needed. These are Case SENsitive.
http://nwvault.ign.com/View.php?view=mo ... il&id=4215