Just to be clear, the Sturmpioneer along with every other infantry unit did not see a value change. They are worth the same, their stats were just optimized to better reflect their intended functionality. i.e. Sturmpioneers lost damage for durability. The idea is that when they close into an enemy unit, they receive less damage, therefore increasing the likelihood of having a whole squad over a partial squad. Their short-mid range damage output is already high enough in most cases that the reduction in damage that was applied will not result in the squad losing the given engagement.
So Assault Engineers haven't seen any value change?
The problem is that sturmpioneers still lose entities when closing in, the trick was to close them in while enemies are busy dealing with e.g. Volksgrenadiers. You can could close them in unharmed or with minimal damage and then do a massive amount of damage due their glass cannon status.
This was enhancing combined arms and proper unit positioning.
The same way was used to clear out buildings with maxims, bait with volks, clear with SturmPios.
Now it takes more time to clear buildings and it leaves the enemy rather unpunished when his flanks were open.
It might doesn't make any sense to use them for close ins anymore at all. Maybe is just better to keep them in a huge blob together with volks on mid range. So it's rifle blob against okw blob....
I see you wanted to change them in a way that they become less RNG dependant and deliver a more constant performance, but that doesn't harmony with the high rish / high reward design of the OKW faction and feels therefore like dumbing down the whole faction.
Now you have a mediocre unit that will reward you less for risks.