Ripzerai said:
But they'd be wrong. I say that not out of arrogance, but this argument has gone on for quite some time now and no one's managed to say why it isn't nonsensical as it is.
Contrariwise, you have not offered anything that demonstrates it to be nonsensical in anything but a subjective way.
Cutting to the chase here: your view is subjective.
You've said a lot of stuff, but you haven't offered any reason for making them less or equal in power to balors other than "It can be rationalized, it can be scaled, I don't see what the big deal is."
Well, you put it rather mockingly, but that is really the sum of it. That you don't find it compelling does not make it "not a reason."
I'll add (again) that I don't necessarily think that it's desirable that they be less powerful than Balors. I think it's desirable as a starting point they should be in striking distance of a 20th level party.
I would not have made the choice myself to put any of them on lesser footing than a balor. But I think that on the scale we have here, it's not anything to get upset about. It would take minimal tweaking to put them over a balor, and even if you don't, I see it as perfectly within reason that a being that is only 1 CR less than his mightiest servant could rule that servant through guile and treachery, or other more exotic means. I would not find the same scenario plausible if the demon lord was 5, 10, or more CR less than the balor.
It's not a big deal, it can be scaled, and it can possibly even be rationalized (anything's possible). That doesn't mean it's a good idea, or that it's something that's necessary to serve the broadest possible audience. It actually unnecessarily narrows the audience.
If you are just quibbling over 2 CR, I think you are make a moutain out of a molehill. At any rate, as I already pointed out, I could see that raising their CR by 2 across the board would probably be a good thing.
Setting aside that last 2 CR, I must renew my insistence that putting them within striking distance of a level 20 party makes it usable by the broadest audience possible. Epic level is only played by a small subset of the D&D audience, and the higher the CR expectation you have for demon lords, the more likely that you fall into the "mortals should never be able to challenge demon lords" camp, making their combat statistics, again, useless for anything other than armchair musings.