I think Faust can't be farmed anymore being one of those master monster portals now. The same goes for regular Mushmom.
Also, I've found that Robo/Master mix of the Aparatus Room is really good for low mobility classes like Warriors because of only 4 platforms (bottom right of the map) that have usually 5-6 robo on them at a time perfect for slash blasting (I trained from 55-65 in about a day here on my fighter.)
http://global.hidden-street.net/map/...-aparatus-room