Arlet has a
CPLD-6502 that fits four XC9572XL so it should fit EPM570 with resource left over for SBC support functions. That should be an interesting project in itself.
What I am currently working on is VGA beam racing 6502 at 25.175MHz, an enhanced version of
VGA65. It is similar to your cheap video project with 6502 doing actual scanning, PS2 input, audio output at 31.5KHz interrupts and then work on application during the vertical retrace period. The original VGA65 is done with a 64-macrocell CPLD and I/O limited PLCC44; I should have much more CPLD resources with 100-pin 570-macrocell CPLD.
Bill