Lanefan
Victoria Rules
One thing to clarify - are you talking about mid-campaign changes or pre-campaign parameters?Why isn't "something in between" a valid answer? I've been playing that way for almost 40 years now, except those occasions where a dm decides the players opinions are irrelevant. You just listen to each other and explain why you want to make the changes you want to make. At the end of the day the dm gets final say, but that doesn't empower them to make any decision they want regardless of what anyone else thinks - and if they do, they're a bad dm.
For major mid-campaign changes I largely agree with you. If, for example, I've signed up to play a bog-standard game in Greyhawk and a year in you decide to shift the campaign to Eberron and use that setting's rules I-as-player have a right to be a bit hacked off because that's not what I signed up for and Eberron isn't a setting I want to play in.
But for pre-campaign parameters there's no discussion required or needed. If I design a setting with no Gnomes in it then that'll be made clear when I invite you in, and should you accept said invite you ain't playing a Gnome in that setting no matter how much you bribe me. Ditto for houserules (a big deal here, as about 95% of my game system is houserules these days). I-as-DM get to make those decisions*; and most of them are made long before I start inviting players into the game.
* - whether those decisions are correct is of course an open question that won't be answered until play is well underway - the trial-and-error method of game design, I call it - but that's another issue entirely.
