I don't think Benitez is a bad manager, just not right for Villa. Houllier made it abundantly clear just how much he still loved Liverpool when he first joined us here, and managed to alienate a large portion of Villa fans as a result - most of which he'll struggle to ever get back on side. I don't have a problem with GH having a fondness for a former club, but ramming it down our throats was not a clever thing to do.
So the idea of Benitez coming in... someone else who ended his time at Anfield on a low note, someone else who still openly professes his love for all things Anfield, someone who still lives in the area (I think?) and who has recently been quoted as saying he'd love to go back and manage Liverpool again.... please no, keep him away from Villa Park.