I agree Nee.
Abilities are easily made to be balanced. Also, I don't see that OKW commander as OP.
Camo Ability-think of Soviet AT gun camo, if it costed muni. This wouldn't be ambush camo like on JLI, Partysans, etc. it would totally remove unit from combat. Uses of ability would be recon/infiltration, not really combat unless your ambushing a tank.
Black Devils-your right on them being Allied Falkimjager. (One black, one green devil.)However, no AT snare, lower alpha damage when they appear, and no vet 5. In return they can go through snow. I also have no qualms with Black Devils being frail/expensive.
Radio jamming-I think it would be a neat ability of done properly.
The thing about the commanders that offer "sneaky" abilities, is that they are not "sneaky-oriented" commanders, they are just commanders that happen to have a few abilities that allow for a sneak approach. This is very different from a commander whose theme is geared towards ambush and stealth. I mean the only really sneaky thing about Salvage Doctrine is Jaegers. Fallschirmhjaegers are also just one unit call in (and very expensive) among others. Eeverything else is conventional unlocks. Signal Relay from Elite Armored only affects tanks, and
More importantly, less stealth-oriented abilities means this commander idea becomes more useful in matches where stealth may not be the best approach. This naturally makes the commander much more useful because it can be applied in far more scenarios than just investing munitions to stay hidden...which all means nothing when OKW can just deploy an IR halftrack or use Artillery Flares.
Giving the cloaking benefit only from officers reduces the need to invest munitions into every unit, while sill encouraging good micro to keep units alive and stealthed. It also means Incendiary Bombing Run doesn't have to justify itself by trying to go a sneaky theme, because the theme is no longer sneaky, but rather another random commander that happens to have a sneak attack option up its sleeve.