The comparisons I made was Marks 1 to 6 armour to Marks 7 and 8. And SoB armour has the same protection because its armour component is made from the same composite materials as found in Space Marine armour. Who says that SoB armour is that much lighter? A square inch of SoB armour will weigh the same as a square inch of SM power armour. It's the subsystems that are different. No neural connections, no extensive lifesupport, no autosenses, and that is just the tip of the iceberg. You're being somewhat ridiculous here. Plus it is because of a misconception on your part. Well flak armour is poor according to the Lore. Though according to some it is little better than cardboard. It is common sense. You just missed how it is common sense, apparently because of some incorrect pre-conceptions. One bit of Lore you need to remember is that the Imperium was at its technological height near the end of the Great Crusade. Since then it has been in decline.
Don't use FFG as an example. They're a third-party manufacturer, their lore is only canonical as long as it doesn't contradict GW, BL, and FW. Roughly speaking an Astartes without his armour stands half a metre taller than the human average. If the average is 1.8 metres than an Astartes is 2.3. In their power armour most humans reach chest height on an Astartes. Though there is no uniform height for Astartes, only an average. Sororitas are normal human height without their armour, in it they are a few inches or a handful of centimetres taller at most. Cables on Astartes power armour are themselves armoured giving them a far larger diameter than you estimate. Supplementary systems include a waste reclamation and recycling system, electromagnetic systems for mag-locking wargear to the armour as well as magnetising the users feet so they can walk on a ships outer hull, shock absorbing systems for when Astartes drop/jump down from a height, and there's more systems than that. But seeing as you've made up your mind I am sure you will not post in this thread again.
That should put the average armored human at 2-ish meters then. As for Sororitas... Yeah, I'll concede the point that they're going to be fairly short, even in power armor. But as for armored cables, are they armored throughout the entire system, or just when exposed? It would make sense to do either, seeing as how it's combat armor... Then again, most illustrations of, say, Mk.III plate have the cables not much thicker than a few centimeters or so. While the AdMech is inefficient and slow, they aren't stupid, so I was giving them benefit of the doubt when it came to internal threading. One would hope they'd ditch the armored sheath before compromising armor integrity for the sake of expediency. As for supplementary systems, a general rule in sci-fi is that waste reprocessing and recycling systems can be including under the umbrella term "life support". I know of maglock boots, and the shock absorbency systems (both are a given in sci-fi armors though), but I've never really seen it explained *how* the weapon maglocks worked. I always figured it was on the weapon side, given how difficult it would be to locally magnetize a section of conductive armor...
Somewhat off topic, but I love that picture. It's so sweet and romantic, until you realize that there is an entire hive burning down in the background; given the presence of the grey knight, there has almost certainly been a daemonic incursion that will result in the sterilization of the planet. But hey, here's a pink rose.
