1. Forward Retreat Point's cost is reduced to 200 MP.
"In the past, the FRP was 300 MP due to the fact that you have free medics. Now you have to 100 extra MP to unlock the medics, shouldn't the price for the FRP be 200 MP?"
I would agree, especially when you consider that USF in comparison gets three free units- the officer squads that allow for map presence as well as unique abilities; OKW for their part used to get "free" abilities but only once their trucks were deployed; and the immobility and locality of these abilities (which aren't unique in themselves either- they are basically the idle passive versions of Sturmpioniers repair and medkits). This also means that USF players by virtue of teching to T4 and getting Major "for free" also gets FRP for free.
Now of coures you can say they are only free the first time you tech up, but that's the same excuse for the OKW trucks, but unlike officer squads, an OKW player absolutely needs HQ trucks up and running; they don't require 0 Fuel when you deploy a T4 for the second time.
2. Sturmpioneers: Remove the Panzerschreck upgrade; make flamethrower upgrade non-doc.
"Sturmpioneers right now are carrying to many duties and most of time, many just won't give them Schreck since it's too risky (You removed its mine-clearing capability). By removing Schreck and give them non-doc flamethrower, they are now act like Ost's pioneer: An engineer unit excels in close combat and dealing with units in buildings/trenches/emplacements"
Volksgrenadiers already have the incendiary grenade, which arguably replaces the flamer role, even if it costs munitions each use and results in overall higher munitions expenditure for OKW. Which for your part you have a good point: the lack of flamer puts OKW at a munitions-cost disadvantage, especially when accompanied by having to equip Sturmpioners with one of two upgrades (mutually exclusive, no less), while also expecting to perform in combat AND construction/ repair. Way too many duties for the game's most expensive builder squad, and they don't even get the benefit of larger squad size.
3. Volksgrenadiers: Replace 2 StG44s package with a LMG 34 upgrade; replace incendiary grenade with normal grenade.
"I still think that the double StG44s are great, it's an overall increase in performance after all. However, volks is a long-range units and become defensive later on in the game due to the fact that rifles/penals are better at attacking through open ground. The StG44s would help remove closing-in enemies, but we already have Sturmpioneers for that job. By giving volks LMG 34, volks will now excels in long-range combat while Sturm will helps with dealing with CQC units. On the other hand, since Sturms are now effective at dealing with units in building due to change 2, there is no need for incendiary grenade."
Only thing I really hate about the StG44 upgrade is that it locks out both weapon slots, reducing the Volks' potential for versatility that OKW players need to prevent picking up dropped stuff that would make them more useful or more powerful.
Obviously your LMG34 idea is to make them a bit more like Grenadiers, in that case I wouldn't mind, but a five-man squad five vet5 would claerly be much more powerful than the Ostheer variant.
4. (Debatable) Replace the Raketenwerfer with the 50mm Pak 38 (https://en.m.wikipedia.org/wiki/5_cm_Pak_38) which at Tier 1 (The Base HQ) but unlock and buyable after setting up a truck.
"The Raketenwerfer is actually very good in my opinion, the only problem I have would be its aim time. Sure we can fix the aim time but then we would have a stealth, quick-aim, quick-fire AT gun that would strike at any time (Especially after vet 1). So unless its aim time can be fix well enough without make it being like above then sure, no need for this change, but according to what I have seen, many people seems to prefer a frontline AT to a hit-and-run one so probably this change would be better."
More practical idea would be to simply buff the Raketen's problems to comparable level of other AT Guns. If your car has been fitted with the wrong tires, it's far more practical to just change the tires than buying a new car, or in this case, inventing a new car with the sole purpose of replicating the first; the only real unique characteristics about Rak43 is able to retreat and cloak.
Anyways end of the day, making OKW a Ostheer clone is basically fraudulent: everyone bought the OKW DLC faction because they wanted an Axis faction that operated differently; if you want to play as Ostheer you just play as Ostheer. Why buy X faction and desire the the qualities of Y faction, when you should have just bought and played as Y faction? There is also the fact that Relic would be legally obligated to re-write a great deal of their advertising to conform to the new standard- that is, they operate just like Ostheer. It's no wonder they drag their feet on changes: change too much and they become a faction clone; change too little and the bitching continues.
Vanilla factions having "best design" is only because they are the first foundational ones- their design influences how future factions can be designed. Under an asymmetrical design standpoint, this naturally means that after producing product X and Y, the product Z needs to be close to X and Y, but distinct enough to not ruin the balance of between three. Not exactly an easy task, especially with the crew that Relic has to work with (not implying incompetence but rather limited resources and freedoms needed to implement). This also leaves Relic with choosing one of two terrible choices: make the vanilla factions good enough to sell and roll with it when trying to design new factions (which they did, and unsurprisingly having trouble with), or plan the entire thing from the start and sell incrementally, which they might also have done and paints the "milking for DLC" targets on their back...which they also did.
This wouldn't even be that bad if it was just done well. Difference between Relic and companies like Blizzard isn't the future-product/ DLC milking scheme, but rather if said schemes are actually good products; Blizzard isn't having a troubling time balancing out and debugging Reaper of Souls and other post-release game changes, biggest of all reasons is very extensive (and public) testing that is separate from the live game.