Aside from the fact that I'm not interested in buying my kids restaurants, I fail to see your point. You make sure you sign with a company that takes you in because you can be creative and create besides using the toolset. If you're completely new to the industry your own ideas of good design will need to be nuanced by learning under experienced higher-ups.
You're talking about hypothetical situations where producers have creative control, and other comparable scenarios. If you want to shut up and make sure you keep your job by pleasing your boss even if he makes a bad decision, you're not really a designer, and you're not doing what you're supposed to. At work I've always met decisions that seem off with questions and concerns. Usually there is a good thought process behind the decisions but well argumented alternatives are never simply ignored.
Hypothetical?
Unfortunately, I don't think... Because there isn't a Game Studio that works the same way, most of them use similar (different) titles for job position, but the roles are mostly different. Plus, each Game Studio does process differently, even if we may think they work in similar ways and each process does affect the Creativity differently (I mean, our Creativity as level Designers or else). So, even if you do well document or argument an idea, the guys above may just do not care at all and are free to refuse you could be right.
- If your Studio is independant and got a contract for a game based on a Film, it's one type of process.
- If your Studio is independant and does work for Microsoft to produce a specific game it's a different process.
- If your Game Studio is owned by Activison, EA or Ubisoft and does work closely with the HQ it's a totally different process because the HQ may just change everything at anytime, they are you real Lead Designer and Producer and your Studio does only have a little impact.
- If your Studio is owned by Activision, EA or Ubisoft, but they do let your Freedom to produce the games you want and they only act as Publisher (in other terms), it's a whole different process.
- If your Game Studio is totally independant, managing his own Budget, release his stuff when it's done and needs to find a ncie publisher, it's another process.
In each of thsoe process the impact of your Position changes. Plus, if a Studio does have a lot of Employees, each of them does have no or just a little impact on the ideas and production. In a smaller Studio, each employee may get easier the opportunity to impact the Game and Quality, because they do not jsut act as slaves.
By chance, here in Montreal we do have various types of Studio and I got a few friends a bit everywhere. Plus, if you are Junior, Senior or lead the job differs depending of the Studio too, each of them does get more or less the opportunity to be truly creative. However, everything may also change depending of the various Projectsa Game Studio could produce. Depending of the Platform and the type of game you develop, it may change pretty much everything. If you do work as a Level Designer on Guitar Hero: Greatest Hits, it isn't the same as making Unreal Tournament 4. The creativity isn't the same and doesn't work the same way.
In conclusion, it does vary a lot. The hierarchy behind a Studio does affect that Creativity and how much you could give. Sometimes a Game Designer will only execute the demand of his HQ and wouldn't even have to do somekind of Market studies. Sometimes, even the Producer may act as a Game Designer and filter what may be good or wrong and much more. it is never the same... I'm working on my fourth project and each of them was completely different. I never had the exact same role and I didn't contribute the same way [Game Design, Level Design or just produce from a Layout that was already done].