Well, the next version the Hollywood will bring us some nice surprises(I'll hope) and Hollywood is multiplataform, the only problem is with Classics without graphic card.
Correction: The only problem is that Classics and non-Classics are incompatible with one another.
Classics with graphics cards still suffer from low bandwidth on their busses due to old architecture. The Amiga Chipsets were designed to work within those constraints while the GFX cards were not. It would be hard to imagine getting good performance out of a 50 MHz processor when most non-Classics have a 500 MHz or faster processor.
IMNSHO, you're better off treating the Classic Amiga as a separate platform from most of the NextGen hardware.