If the PS1 core gets done successfully, there are some major components then which would be completed which make up the Namco System 12 arcade board (https://www.system16.com/hardware.php?id=535), which could then very well be done in FPGA at that point. It's basically a slightly modified PSX motherboard and chips. And the same goes for the Namco System 11 (http://www.system16.com/hardware.php?id=533). The arcade board potential from a working PS1 core is pretty good.
Also the Capcom Sony ZN-2 could be done as well if the PS1 is completed. It actually uses Q Sound (which jotego is already mostly completed I think) instead of the PS1 SPU, but has all the other hardware from the PS1. If the PS1 gets done, it really opens up a lot of other stuff potentially. Add the ZN-1 on there too apparently. Same kinda deal.
To those who are saying saturn is impossible on the MiSTer, I'd push back on that. It's more complex, but it won't necessarily take more space. I do think if we do see it, that it would be in 2022 though. If ElectronAsh and a few others I've talked to thinks it's doable, I'll take their word for it.
N64 is probably impossible on the MiSTer, but Mazamars is making good progress from my understanding on his more expensive development board.
