The casio piano's styles are below pa3x in my opinion...
The integra 7 has the best sounds of Roland, all in one box...
The BK7m has some nice styles, yet in my opinion, the pa3x sounds better...
May i ask what part of the Korg styles you dont like, they are very very tweakble? Why keep the pa3x, if you dont like the styles?
In the end i would go for the integra 7, and use that in combination with the Korg styles...
Outside of your box, did you consider adding Varranger in combination with a windows tablet? It playes all the styles of Roland, Korg, Ketron and Yamaha.. Espescially with the upcomming soundupdate... There is just no multipads with Varranger..