The problem I've seen - and it may not be all of them - is that the high output alternators don't do as well at low rpm. Not all companies release the rpm vs current curve for their alternators, but the ones that are available usually show poor output at idle rpms and the advertised peak rpm is above the 2F redline. Are there "better" alternators than the 80 Series stuff? Absolutely. Do they require even more work and finagling? For sure.
The nice thing about the 80 Series stuff is that it drops in on the lower bracket, so you're not modifying that one. Any other solution opens an even bigger can of worms. And that's fine, it just depends on your appetite for fabrication!
Also, what electrical stuff are you running? I've got a dual battery system, 340W of extra lighting up front, plus extra cabin lighting, a fridge, and multiple USB ports running off a 60 alternator with the guts of a 62 alternator inside of it. 65 amps. Yeah, if I have all my extra front lights on, things bog at idle, but over about 1000rpm everything runs perfectly fine.
Not saying this path is better than another path. I'm only saying the return and the investment are in a pretty good ratio: a decent bump in alternator output current for fairly minimal work. And that might appeal to group of 60 owners.