Imagine if Xevious arrangement got this treatment in here
I've considered it. It's already 68K of course. I actually did the MAME driver for it (Namco Classics PCB) many many years ago, so I know - or at least knew - quite a few technical details about it. I have also started on a MiSTer core for it. But I haven't looked closely at what it would entail, or even if it's feasible on the Neo Geo.