Global upgrades are anathema to mixed compositions.
Making Conscripts cheaper won't fix the fundamental design problem with global upgrades. Conscript upgrades are only cost effective if you build several squads, so there's little point mixing them into other builds.
Why would people build Conscripts when they're rewarded so heavily for not doing so?
thats why i say cheaper
cheap enough that if you have the spare manpower its worth it to throw them into a con squad so you can merge on field, so you can build cover or scare the enemy off. right now if you can afford a con squad on equal termss the enemy can afford a gren squad or nearly afford a volks squad both of whom laugh at you building qa cons squad.
cheap enough that you can start building your mg or penal squad when your building is compolete if you build a con squad off the cuff.
cheap enough that if they die buying you time enough to pull off a flank or hold a point long enough to get reinforcements up its not a massive loss
cheap enough that if you try and merge a 4 man squad into a 3 man squad and a model drops you dont feel robbed becuse you lost the damn squad.