They cost less than Obersoldaten or Shock Troops, they're not expensive. They're extremely efficient for what they do. I agree with OP's assessment, it's similar to the suggestions laid out by Cruzz, and he generally has a good idea of what's going on in the game's files.
They cost 500 Manpower to call on. What in the name of Jesus on roller skates are you talking about man.
Wait just realised about Vanguard. Where they cost a whopping 540 then 360 to call on. I could see a slight buff to their cost maybe to 400 but people asking them to be 450 are clearly overzealous.
1) On the comparison with Shocktroops. They need a cloak to get close top enemy units. Unlike shocktroops their armour is terrible and they drop like flies to Obersoldaten which will usually be on the field by the time you start chugging them out.
2) Their 1 second grenade fuze I feel supports what this unit should be - A high "Alpha strike" unit designed to ambush and potentially wipe units before you react, but only if they are microed effectively. Alternately buff them to an actual gammon bomb. I'd love my commandos to have a 3 second "nuke engines" grenade.
3) Their DPS overall should be toned down and instead they should have an ambush bonus of accuracy. This would mean they have to be used as well... commandos and not as frontline infantry. With the changes to their DPS them camouflaging would not be such an issue. Infact it would mean this units entire point is to be camouflaged. To be honest this unit should be focused more on ambushes and raiding.
3a) An alternate suggestion to their increased accuracy instead of high DPS would be to make them decap points faster than normal infantry effectively making them "raiders".