I have a job too and while I have quite a bit free-time to put into things like this, I really don't have the patience to work half a year on such a thing.
Half a year would be excessively optimistic for a substantial mod. I conceived of Arkalian in November 2005 and she's still well over a year away from completion, my life having flirted with the rails but repeatedly run off over the intervening time.