Going the LibRetro way is only going to make the problem worse and further annoy those who contributed under 'no commercial' licenses, as things like RetroArch basically provides a way for any scummy company to bypass the license requirement by using the 'core downloader' (which probably wouldn't stand up in a court of law on a locked down box, as it's still integral to the product, but all the chinese bootleggers can get away with it because their systems are 'open')
LibRetro based frontends (RA etc.) are making no effort to show the user the emulation licenses when they get the emulators / run the cores, despite the cores being under different licenses to LR/RA, meaning a lot of people then claim ignorance of the situation because the conditions have never been communicated. The maintainers are acting in highly irresponsible and complicit ways when it comes to this, ways which are harmful to the emulation scene in general. RA at targets mass appeal *at any cost* which is a problem.
LR also makes it easy for anybody to make an ad-driven 'portal' frontend, and again claim they're not going against the wishes of anybody (this happens a fair bit on mobile)
LR also brings projects closer to things like Kodi (due to Kodi LR loader plugins) and Kodi already has a terrible reputation for being abused commercially in order to sell pirate TV boxes etc. (to the point where boxes etc. get seized, analyzed, legal action taken against plugin developers etc.) Making it easier to add emulators to these 'all in one' boxes only brings further unwanted attention.
If anything projects would do best to kill off LR support / leave it up to the LR project maintainers, not invest further into it. I've said elsewhere, LR is parasitic and mainly enables unwanted business models, and I stand by that.
Simply changing FBA to a libretro project would strip if of all identity, and take away the ability to provide the user experience you want as well, making more advanced features more difficult to implement as everything has to fit the 'dumbed down' model they present.
Maybe that's not what they intended when they came up with the concept of 'emulators as libraries' but it was very predictable, and is exactly what has happened. I still think it's the single worst thing to happen in the 20 years I've been involved in emulation. I get that it is 'convenient' but that comes at the cost of far too many negatives. (and this doesn't even cover the technical negatives, only the social / economic ones)
Beyond even that, the core maintainers for LR cores explicitly ignore the wishes of the developers of the emulators they're including. The RA devs act like they're the saviours and defenders of the scene, but as soon as we say 'please show the emulation imperfection warnings' or 'please show the license on startup (especially for older cores that are non commercial)' they try to strong-arm MAMEdev into having an official RA core, telling us to add them ourselves if we want them and coming up with a whole bunch of technical BS about why they can't show them rather than simply respecting the wishes of the developers. My experience, and everything to do with them, and LR based projects is overwhelmingly negative, I have more respect for Barry, and after all this that is saying something.