+++++That's kinda the point of being a Space Marine, isn't it? Phenomenal power, itty-bitty living space.+++++
I dont… think it is essential.
While mind controlled attack dogs of The Man with an inbuilt kill switch to shut them down if they express an opinion is certainly one way to spin Marines, I feel there are others.
For a start, unless television has lied to me, such a character must eventually learn to say no and lead a rebellion against The Man.
But we can select other archetypes. What if Marines are more like Arthurian Knights and Marine organisations are not strictly hierarchical military organisations but instead more a loose fraternity of Warrior Brothers? You don't get assigned missions by superior officers, instead rather opportunities for doing epic deeds for the glory of the Emperor come up and Marines petition for the chance to win glory they provide. Or just, yknow, head out on their own.
You can see this in the suggested structure of Deathwatch kill teams, where there is no official chain of command but rather individual Marines step up to take point as their skills dictate on an ad-hoc basis. Which is totally a conceit to make a roleplaying game easier, but this is a roleplaying game .
And you can mix and match.
So a kill team could consist of Kurt Russell from Soldier, Lancelot, Soap McTavish (or Andy McNab) and Eric Bloodaxe having an adventure together.
From a purely practical point of view, people who want to indulge in a spot of power fantasy (which I think is a totally valid way of playing Space Marines) are not going to appreciate having it rubbed in their faces that they are totally someones ***** and they should shut the **** up and know their place.
+++++And that any GM who so much as implies that the player characters aren't the rampant manly god-kings of everything is an evil tyrant?+++++
Well, I mean, what is wrong with playing a rampant manly god king every once in while? And when are you going to get a better chance to play a rampant manly god king than when playing a mighty Space Marine?
And if your advice on how to handle the situation starts to sync up with the guy who doesn't like Marines and admits to trolling the forum…