Games will have bugs or not run correctly. You might not have noticed it, but I did. It depends on the game.
I agree with that between 0.36 and 0.78 it nearly doubled and between lr-mame2000 and lr-mame2003 I would think a shoe in for the latter and is considered the gold standard in certain aspects except maybe vector where AdvMAME outshines them all. I do agree to that FBA seems to run Neo-Geo, Capcom, Konami games better. They just seem to run smoother for certain.
I do also use multiple emulators too depending on the game. Mainly lr-mame2003 roughly 300 or so games with aforementioned options of shader and analog d-pad support. AdvMAME for vector, FBA for Neo-Geo, etc.
The original author of mame4all-pi (squid) had a majority of the games running at 100% without frame skip. It's been a hobby of mine since the late 90's. I do faithfully download the split updates every few months merge it and join the torrent. That includes the CHD's & extras, etc. I think it's close to 400GB now. It's where I spend most of my time when it comes to emulation.
That's what I was pointing out is the binaries (ROMs) are mostly 100% identical between the two version which are only 3 years apart. I don't believe the driver/board support emulation improved that much between those versions but they went crazy with additions.
You would have to be more specific on what exact games you find buggy in 0.37b5 that work differently in 0.78? My main point is that mame4all-pi (not lr-mame2000) is still very relevant if not a choice not just for the familiarity and support for being so widely ported but also the input configuration is still superior out of the box it works. Meaning there's certain configuration scenarios lr-mame2003 can't do...yet or at least not easily as I believe you will loose hotkey functionality if you "nul" all the Retroarch inputs to rely on lr-mame2003 inputs alone to correct the issue. :)