Have you tried to run SP towards riflemen/IS holding still? Spoiler alert: Its not even funny...
At best SP have to hide and flank, and its powerspike drops fairly fast, they also become the most expensive engi unit ingame as a main drawback. Loosing SP is very bad too. But you already know that, isnt it?
You mean OKW's starting unit can't walk up to a mainline infantry unit, in an advantageous position, and expect to win easily?
This clearly has to be corrected ASAP.