I assumed that things like transforming roles and hidden information weren't used here, but that was obviously a faulty assumption.
This is the first time I've seen a motivator (not that a motivator is bastard in the slightest anyway) and maybe the second time I've seen hidden information that I can remember if SkyPal's VT pm counts as one, which it really shouldn't since it should have been painfully obvious upon receiving it that he could not truly be VT. (I've been playing here roughly 4 years I think?)
Anyway, I think you're really overreacting. You say it's not up to Dormio to decide which one is "fun", but I think most people would agree that what he was trying to avoid is indeed "not fun". People getting carried away with roles is VERY not fun, it's usually pretty irritating, and they tend to get carried away enough that it's just stupid and not even going to have a better chance at catching scum than throwing darts at a board. And even when they don't get that far carried away, it tends to remove the actual mafiaplaying aspect of the game to a significant degree, and then even the people still trying to play normally have less to work with because a decent amount of the players are doing nothing but rolegaming over Actually Playing Mafia.
Roles are fun, having them is fun, many of them ARE there to help you catch scum, but it's important for the mod to try to stop them from having a high chance of being able to take over the game. (Also everything I say is only from MotK situations and are not meant to apply to anywhere else since I've never -played- anywhere else) The players WILL be quick to jump at a chance to let roles take over the game, and they'll probably handle it stupidly and guess everything wrong and give the other faction the win. (It's not always town being dumb and losing to scum. Recently we had a ITP win from purely this when he was the mega-obv-nottown like four days before the game ended.)
I believe you can have a game that limits or obviates rolespec entirely without being boring.
Limiting rolespec without being boring is basically the entire point of what happened here, and
Giving everyone a power role isn't the obvious solution, and neither is creating roles which are designed to subvert expectations or are too original to speculate about.
Power roles to everyone isn't a solution, it was just that the point of the setup is also that everyone gets some form of PR; it's kind of nice to /in knowing you're not going to be VT and have a nice chance of landing something that's even pretty cool (hopefully). Creating roles designed to subvert expectations or being too weird to speculate about isn't bad either? I'm not sure whether you're just saying one should stick to the standard list of roles or not, but that'd be pointless and limiting, and most of those are pretty strong (which would be bad)
IMO the best kind of role madness game (unless you specifically are looking for literal Madness, which can be fun every now and then, but MotK gets enough of it as it is) is one where most of the roles are fairly tame (aka have little real power effect on the balance), and there's at least a couple pretty abnormal roles. My previous setup I Wanna Be The Sereliest fit that and so does Dormio's here (to an even larger extent), and IMO Dormio's setup was perfectly fine. Then there's stuff like Shadoweh's mafia where it turned out everyone was actually functional vanilla >:V (It was all Role backups, and Role enablers, and other silly things. It was actually still really interesting since we didn't realize until d3 or d4, and claims made were still powerful things. Plus she also put in an opt-in feature to get a Post Restriction in exchange for nighttalking and had regular day events, a special lurkerkill system, and a post word limit to deal with the current wallposting issues)
aaaaalso by the way
"I made a complex game with cool roles but I want you to find the scum without talking about the cool roles I made"
Almost all of the roles in this game
were very weak, at least in terms of finding scum with, they basically HAD to be Motivated to not suck and half of them still didn't do anything then. So yes, he made a complex game with cool roles, and you still won't be able to find the scum with them even whilst talking about them beyond what you'd get in a "normal", only-a-few-PRs game with mostly VTs, without extra effort on his part. This is Good Role Madness Setup Design imo, even if this setup is even weaker than I'd normally suggest. I mean the VT pm and Zakeri abnormal backup with rawr thing might not be something I'd put in a book of Good Design but they really aren't a big deal either
tl;dr, Role Madness is fun but you probably shouldn't give the players a whole lot more power than they'd have in a setup with two thirds of the town being VT and the others being strong PRs. Otherwise you get Actual Madness, which is only fun to have every now and then (and we get it fairly often already) Especially, especially considering that it usually devolves into people yelling at eachother about the setup and trying to outguess the mod about everything, getting things wrong, and then leading town to smother itself to death through incorrect assumptions about roles.