One of the main problems with the design of Fallschimhager is that they have not real weakness.
Other high damage infantry units are either only good at one range like Shocktroops being only good at close range or Obersoldaten being good at long range or have a lack of anti tank weapons like Paratroopers, Obersoldaten or Shock troops.
The easiest solution to give Fallschimjager a direct counter would be to remove the Panzerfaust. Now they can still be really good at all ranges like they are now, but still directly counterable if unsupported.
+1
They're the only elite infantry with a snare anyway and it's kinda cheesy when they can use it out of camo too.