But back to the point about 5 posts ago regardless of how scary it is to face your own fragile mortality as a soldier watching them fight to general populous they are the stuff of myth and legends.
We know what implants they have and the heraldry of a number of chapters but your average citizen knows none of these things, knows nothing about the difference between the chapters or their abilities. To them they are as likely to have heard that they can kill with a look, breath fire, fart poison or some such. So they are give them a wide birth.
See, this is what Marines look like to people on the outside.
But for a Marine roleplaying game (and Marine focused novels etc.) most of the time we are going to be on the inside.
Er, slike how to most of the Imperium Inquisitors are legendary figures who swoop in from nowhere to dispense terror/enact the Emperors will.
But those on the inside know that there is a constant war being fought between Inquisitors over what is best for the Imperium. There are factions and politics and secret battles that the average citizen doesn't see. That Inquisitors themselves have distinct personalities and ways of doing things.
So, we would want the same for Marines. Even if they look like impassive Angels of Death to the casual observer, amongst themselves and their peers they have a lot to talk about and want and politic about and disagree to the point of shooting each other over.
(Generally, I think it is safer to er on this side of personality. If you write someone as looking like a personality free killing machine, people seem to assume that is what they are. Where as if they were fighting their battles on twitter, there could be no argument that they think for themselves.)
...every single one of them is a Space Marine, a guy who single handedly can take on a modern infantry division with ease... -Alan Merrett, Head of IP, Games Workshop
In Fear to Tread there's a Remembrancer who wants approaches a heroic Blood Angel Apothecary, wanting to make a regular comic about him and his exploits. Because he survived a mortal wound while rescueing a dozen people.
The Space Marine, naturally, doesn't get all hyped up on it, and start thinking about his fans, and the attention of amourous females. He's pretty humble, and even finds it a little odd. But lets him go ahead and make it. I still have much more of the book to read, though.
"Would you like to travel across entire sectors in months, rather than years? Would you like to blast people with warp energy? Would you like to have an extra eye? Come down to Fabius Bile's Gene Emporium, and become a New Man!"