The PPU is definitely complex but the NES has the benefit of being much, much, much better documented than the GB which is honestly a huge advantage. The NES a

The PPU is definitely complex but the NES has the benefit of being much, much, much better documented than the GB which is honestly a huge advantage. The NES also has a bunch of complex cartridge mappers but you don’t necessarily need to implement the most complex ones like MMC5.