Conscript have start with received accuracy of 1.09 which is the worse for Soviet units
CE, Penal, Partisan all start with received accuracy of 1.
While being far cheaper, available earlier and having cloack.
Their utility includes:
They are excellent scouts with extra vision and cloak
They are dirty cheap and ideal for ambush with cloak/mines/grenades/and concussion traps
They can become Ambush AT units with tank detection/mine/snare and shreck
Two grenades both DOT and HE
They can heal other units or themselves
They can lay wire
Their increased molotov range at vet3 is worse compared to cons throwing speed vet, the animation takes so long that the range buff isn't as helpful.
Ambush bonus applies to Shreck also so they do not really miss the much once at vet2.
Tank hunter partisan did not get reload bonus they used to get 10% penetration bonus.
In sort the unit is cost efficient and remains useful though out the game either as an AT unit or a scout/ (ambush unit) and simply do not "scale horrendously". As I pointed the unit simply can not carry the commander.
I said they scaled bad and had bad final RA which means vetted RA. Cons with VET are .71, Penals are .77, CE are .77 and finally Partisans at .83. These 3 units are available before Partisans so they have already started vetting. To pull off a few of the things you mentioned requires a significant micro payoff to work while having a high chance of squad loss due to bad RA and small squad size. Also 10% penetration was Vet2 for Tank Hunters, at Vet3 they got a 20% reload bonus along with another 23% to RA according to the Vet Guide.
A lot of what they bring Soviets don't really need as T1 can get sniper plus flare for vision and T2 can get mortar flare. You can go Tank Hunter doctrine and get a better AT cloak unit and like you,Katukov and I said the other commanders are just straight up better due to reasons you and I have stated.
I find the commander really only needs small tweaks as it could potentially synergize nicely with T1 start. Switching out Anti-tank ambush for Tank Hunter Ambush along with changing the AT upgrade to Triple PTRS would go a long way to making it more useful.
Radio Intercept - Naturally lends itself to T1 start and helps keep the player aware of any possible counters to sniper/scout car.
Tank Hunter Ambush - This would buff the commander a bit since it doesn't get any premium tank, fits in with the quick hard alpha strike of the commander.
AT switch to PTRS- Shreks/Zooks are horrible inside vehicles so doesn't really help to much so they force a more static play form Partisans. Using PTRS would allow Penals to remain AI focused while the cheap unit gets placed in car for LV hunting
Spy Network/Mark Target - This is where the PTRS will really shine. In team games or 1v1, Spy network could be used to locate weak high value target like damaged tank or rocket arty. A PTRS Squad could spawn closely, upgrade and once spotted with vision Mark Target along with initial volley could take out unit in one or two salvos. At max range Vet0-2 I would expect the PTRS to perform better out of camo and similar attacking from camo. The Shrek wouldn't have the same reliability until VET3.