What are Space Marines - to you?

[The Lost Son]

So whilst trying to decide upon a Chapter (suggestions are welcome) to build and paint a few thoughts have been going through my head and I wondered what other people's take would be. 

Obviously I would assume this being the BnC that the majority of use are aware of what a Space Marine is in broad strokes, but it's their ever evolving origins and archetypes that's currently got me thinking. 

 

General vibes:

At the core the Adeptus Astartes are gen hanced trans humans. Taller, stronger, made for war and generally better than anything else that humanity possess (excluding Custodes, Mechanicum, actually this list is pretty long now that the background is more fleshed out than when I started in 3rd). 

But....... 

Are they knights, brain washed child soldiers, beacons of the imperial faith or something else. 

This is what's been ticking away in my skull for a while now and whilst some chapters are very much in one camp or another I feel at best it's a bit muddy. Personally I'm currently leaning more towards knights in space, but not in the sense of shining steel and fair deeds more that the codex is their chivalric code. It's always?(as far as I remember but please correct if not) that the main purpose of the codex is to blunt the effectiveness of Astartes in centralised command. I'd also image there's a fair few chapters in it regarding not murdering everyone because you had a bad day in the battle barge. I think what my interpretation of this archetype boils down to is that they aren't hero's in any sense other than accidental, they are only lauded and glamorised by the Imperium because it doesn't seem them up close and in action. Yes they serve the purpose of their creation but it's far more destructive and alien than humanity would really understand, luckily the galaxy's a pretty messed up place so these beasts have a purpose that keeps them busy and mainly stops and grander designs if they chose to look back towards the empire. 

 

So that's pretty much my current take would love to hear how anyone else sees it.

[Adeptekon]

They're Space Crusaders to me. Not sure about a few chapters on mental health being in the codex astartes, but pretty much all of the former legions either do what want or need because the Imperium is always at war, so there's always an excuse for an exception to the rule. Guilliman of all people could probably muster 10k in marine forces  when you include successors and serfs, not including the Imperial ones he commands.