The Shield TV takes microSD and can pair with Xbox One or DS4 controllers so you're not forced into getting theirs. It looks like there are also MAME/FBA apps but I don't know how good these are.
DS is the other one I'd mention as being well implemented with good performance (of course not ideal on a normal TV with controller) and of course you're good for PS1 and everything older too. I was shocked as to how good those specific 4 were after years of messing around on other platforms where nothing seemed to 'just work'. I have the Nvidia Shield TV (2019) which I'd mainly bought as a streamer and then to mess around with emulation.
