I've always wondered what it would be like if the Imperial Guard managed to develop a relatively cheaper, weaker but still highly effective multi-role version of the Space Marine armour, and mass produced it.
Within this fantasy of mine, I thought that maybe on the further reaches of Imperium space, a different prototype pattern of power armour would be developed to
a) vastly boost the current performance and survivability levels of conventional IG frontline troops, with a focus on armour/gear modularity, especially commonality between parts so cannibalising for repairs while in the field is easy, and requisitioning spare parts out of field are also cost effective and hassle free.
b) Offer an extended lifetime of service to the Emperor for troops that have been crippled in battle. The IG Tactica armour would be able to accomodate amputees via a electronic gel interface membrane, without need to surgically graft the user to the armour. The armour can also switch to an autonomous combat mode should the wearer be killed, and the onboard tactical AI still functioning, in order to continue the fight.
Another feature of the armour pattern is an integrated second AI and servitor arm system inbuilt into the backpack. This both helps with load-bearing, combat multitasking and construction labour. Each soldier could thus effectively perform the role of a combat engineer, medic and stormtrooper all in one.
And no need for commissars to keep the troops in line, when you have an onboard AI that would gladly take over the reins!
Also for fun, I redesigned the Bolter somewhat so it would have, to my mind, a more straightforward layout and construction. At least the chamber, ejection port and barrel line up (That's been bugging me for years.)
Google Sketchup + Photoshop
Maths for the masses... 1 Space Marine = 500 standard IG
1 Space Marine = 100 Power Armor IG
Over 40 billion IG + Power Armor for each IG = Dead Chaos Legions
Apparently, vanilla AIs have a tendency to fall to Chaos. For some reason.
The Machine Spirits of Imperial Titans are actually complex enough to develop personalities.
That said, there does seem to be some overlap.
regiment variants would be a great idea too, imo
Abominable Intelligence(A.I. forr short) is a term used by the Adeptus Mechanicus for an adaptive, self-enhancing, factitious intelligence with its own consciousness.
During the Dark Age of Technology, these intelligences rebelled against their human masters, leading to bloody wars. Since that time, and by a personal decree of the Emperor himself, it has been forbidden to fabricate or service those machines that are able to think and act independently.
A.I. is not to be mistaken for the machine spirit that has parallels but basal differences - namely, no ability to enhance itself.
(that said, i never play the IG. umm.)
Those are concept art for the Elysian Drop Troops carapace armour
But for the most part, power armour isn't really that necessary because all of the crazy stuff and the crazy battle constitute only about 1% of the actual battles that go on in the 40k verse( in fact, majority of the time, the Imperial Guard fights typical planetary rebels that don't even have lasguns) so all that extra technology isn't that necessary.
I can definitely see this armour as a reasonable marines armor though!
However, they do like their bling a bit too much...
1) A force multiplier, like a Forge World that doesn't have as many people as it used to.
2) A powerful industrial complex, to increase survivability.
Also, it would probably look less like Space Marine Power Armor, to avoid annoying them.