[moftz]

You could use a Zynq FPGA that has a built-in dual core ARM processor. It has 512K of L2 cache and 256K of memory, more than enough to basically copy the same architecture into that design. It also has ADCs built in so you can implement analog joysticks too. It's also probably fast enough to build a graphics processor in logic. Only thing you may want to keep is the sound processor because there is no built-in DAC so you would need to implement that anyway.