Cons are awful, they just don't do any meaningful damage and with their 1.09 target size they aren't all that tough to begin with, and that makes them sub-par for merge/crewing weapons too.
Let's just move whatever utility Cons have to Combat Engis, and then remove Cons from the game.
There you go, CEs are fixed, cons are fixed, and no more multiple mainlines for Sov.
Make an 'anvil sappers' style upgrade for cons, something like "advanced combat training" or use the 'frontoviki' idea that the campaign has at tier-4 that gives them an upgrade to stats and maybe 2 SVT rifles.
Not sure how that'd synergize with the PPSH package but whatever.
Honestly, this may be the best idea so far. Campaign-style global upgrade to infantry sounds neat
Say, after getting T3/4 (or a side tech) all Conscript squads (both on the field and in production) are replaced by Strelki (or whatever name you want to choose), with new name, new shield icon, Guards Mosins and with base target size reduced to 1, they could even have vet adjusted for the buff if they become too potent at vet 3.
So now you have a choice between faster sub-par units loaded with utility, with the possiblity of them being "promoted" to a much better unit later, or delayed, all around powerful infantry in the form of Penals