If you want something more powerful than MiSTer and have a bit of patience, there is the Replay R2 being developmed around the Agilex 5. - Agilex 5 E-Series 04

If you want something more powerful than MiSTer and have a bit of patience, there is the Replay R2 being developmed around the Agilex 5. - Agilex 5 E-Series 043 (Replay2 phat) has 434,240 logic elements (LEs). - Agilex 5 E-Series 013 (Replay2 lite) has 138,060 Logic Elements (LEs). The website (https://www.fpgaarcade.com/news-2/ https://www.fpgaarcade.com/news-2/) hasn't been updated in some time but the dev now has prototype boards that he's in the middle of bringing up. It is purpose built for arcade emulation and has tons of I/O, lots of memory (both SRAM and HyperRAM), and (on the phat) a PCI connector. One or both (can't remember which) accepts an ARM daughterboard for hybrid emulation. There's a Discord for it you can track down to follow its progress basically in real time as mikej progresses.