Here's my take on Midgard coming to grips with the task of upgrading it's military. The shear size of their army presents a major problem, combined with the worst technical base of the Nine Worlds. While the Chosen Men can be fully equipped with Impalers, Carapace, and Plasma munitions, the standard Guardsman will have to make do with less. Still head and shoulders above the Old Imperium though.
I'll post some Midgard pattern vehicles tomorrow.
Midgard Armed Forces in the Post Imperium era
As the Imperial Trust build itself up after the losses of Fjol IV and the discovery of the Sword of Surtur datacores, Midgard had a notable tendency to lag behind the rest of the planets in terms of equipment. This is due to the simple logistics of the matter. Midgard provides over 90% of the Trust's combined ground forces, and the cost of replacing it's full ToE is simply mind boggling to anyone not used to dealing with Adeptus Administratum sub-sector scale numbers. This was combined with the fact that Midgard had the least productive population per capita, and the traditional manufacturing center of Svartalfheim being focused on building up its own defences. In the name of resource conservation, Governer-General Aelfric Abingdon mandated his logistical officers focus on the cost effective equipment for use against the Trust's likely foes. Combined with the efforts of the Adeptus Mechanicus, with resulted in a series of improved vehicle and equipment patterns that manage to retain relatively close production costs to their predecessors.
It was quickly decided that while the Impaler was a noticeably superior weapon, the logistical benefits of the Advanced Laser weapons found aboard the Sword's datacores outweighed them. The Impaler's greater armor penetration capabilities would be wasted against the projected primary opposition of Trust, the Orks of the Gehenna-Subsector, the Tyranids of the Hive-Fleet splinter ---, and the corrupted Petty Imperiums. Going beyond basic weapons, improved models of both the Flamer and Melta series of weapons were also chosen for mass deployment. Being relatively low tech and inexpensive, they retained their place as the most common special issue weapons of the Imperial Guard.
Afterwords, the Procurement/Logistics Department move on to the rest of the soldier's standard issue kit. Fortunately enough, the vast majority of Flak Armor in use could be remanufactured to higher standards relatively easily. While the benefits came in the form of weight reduction and increased comfort, it was considered to be great significance for sustained moral in extended campaigns. Combined with the earlier discovery of legitimately appetizing form of MRE, Midgard infantry have a surprising amount of field longevity. Along with an improved company level communication system, Midgard's infantry are substantially more effective than they were previously.
With this settled, they then dealt with the matter of expendable munitions. In this, a great many improvements could be made. Melta munitions were outright trivial to implement, swiftly replacing virtually all forms of anti-armor projectile and warhead in productions lines. While it would take more than a century for exhaust previous stockpiles of ammunition, Midgard could count upon effective long ranged anti-vehicle firepower in short order. Plasma munitions were a much trickier matter, but nowhere near as bad as it would have been during the Old Imperium. Perhaps the greatest advantage of the Helheim pattern of Plasma munitions is the dramatic reduction of required quality of materials used, leveraging their one use and expendable nature to the fullest. The technical knowledge requirements are also much lower. Still substantially more expensive than normal Fragmentation munitions, Plasma munitions can still be fielded in significant numbers for high priority and special operations units.
Moving onto the realm of vehicles, the Department had several important questions to answer. The most important question was what level of technological sophistication were they going to commit too in the long run. This was ultimately determined by the projected time table of the replacement cycle. It was estimated that it would take slightly over a century and a half to completely replace the entire current inventory of Midgard, and that while during that time the education and technical level of the production base would improve, it would still lag behind those of other planets. With this fact established, it was decided that any major increments in technical sophistication would have to be limited to where they would be most effective. In the name of expediency, efforts began in developing more conventional and less complicated versions of the contemporary Avernus pattern of vehicles, sacrificing efficiency in the name of cost and ease of production.
Midgard's army remains the most technologically backwards of the founding members of the Imperial Trust in terms of proportion. This is mitigated by the fact that the elite and well equipped Chosen Men outnumber the conventional ground forces of Asgard, Alfheim, Jotunheim, Niflheim, and Musphelheim combined. Midgard's greatest strength (and weakness) remains it's size, with the shear number of bodies that can be thrown at a problem serving as a viable answer to most tactical and strategic problems. It is the anvil upon which Trust's enemies are forced upon, with the dreaded legions of Avernus serving as the hammer.