It should hurt all factions in a similar way. It shouldn't hurt one faction more than other. In case of okw losing engineering units hurts more. And they die similarly quickly irrespective of their higher cost when repairing, for example. You also need them more because of allies who have more spammable mines. Losing two model on overs to a mine will cost you 80 manpower. Allies can walk their infantry in such mines much more freely.
Why does it hurt okw more than say ost? If you lose your sturms you can 100%play the game with out building another one because your buildings build themselves and you have a building that can repair tanks and another building that can heal your infantry. Ost loses their pios aaaaaaaand they have no choice but replace them because they can't repair or even tech up.
Sturms can do much more and do it better than anyone else and this is mind blowing but that comes at a cost. Ate you going to give ost assault sturms because it would be nice if their repair unit could salvage and put their sweeper away? No of course you won't nobody will because they understand that power comes at a cost. Sturms are powerful and pay for it. Don't want to replace them you can either :treat them like squishy expensive infantry and not try and assault the enemy base sector with them so that they can retreat safely OR suck it up if you can't figure out when to retreat them and when their time on the front is too risky and treat the according.
Not every aspect of the game should have EZ mode hand holding alternatives for actually playing the game so that any and all risk can be mitigated. Okw has a building. A BUILDING. that can repair tanks expensive sturms was very much considered in their design.