> all that would do is waste time money and mamedev look evil
The right way is to keep making these systems better than what the other emus offer. That means giving some TLC to the bigger console systems. The built in GUI is 'ok' but not exactly eye catching and in some ways kind of odd to use. One of the top frontends for MAME looks like a spreadsheet. It is the one I use because it fills my need as I like the history portions. I find the realm fascinating because I am like that. However, the Retroarch/libretro, Hyperspin, and LaunchBox GUIs are interesting to use. I would even go so far as to say they are kind of cool to use (which is hard to beat). People want to get a bit of nostalgia. That frame skip trick RA is putting in may draw a few people in. But just the initial look will work better. They are not too gaudy but slick enough to be very usable.
Accuracy counts too. It is a big deal. It is a huge deal. The more MAME does it the more it stands head and shoulders above everyone else. Take Dolphin for example. They are learning the same lessons MAME and bsnes learned long ago. Accuracy counts and fixes bugs. That has drawbacks for MAME though with mindshare as basically things look broken most of the time. That is where these frontends come in. They let people get that nostalgia hit they were after. The downside is people will stick with what they know. They get a subtly broken game. But it is enough.
If you do not know what I am on about here is a 20 min video that talks about what is happening (sorry about the length). https://www.youtube.com/watch?v=IzHeDYfkAB0 The idea is similar. What is being sold is not what the users want. In many cases that happens to overlap with what the users want. But not in all cases. It is why the frontends basically including MAME with a slick GUI in front of it. It is why mame32 hung on for as long as it did. MAME has for a long time made the stance of documentation that happens to play games. As long as the built in usability factor is not great these all inclusive GUIs will continue to exist. MAME did what it did for its own self preservation. Which was to chase off as many 'warez dudes' away. However, to make these GUIs not exist you will have to give users a reason to not use them in the first place.