Age of Strategy Forums

Better Engineering I cost=6 turns= T-34 and KV-1 cost reduce to 1
Better Engineering II cost 5 turns= T-34 and KV-1 speed + req:Better Engineer I
Penal Battalion 4 turns= Unlock Shtraftbat
PPSH 42 6 turns= Unlock SMG squad
IL-2 5 turns=Unlock Il-2
PTRD-41 3 turns= Unlock AT rifle
Tupolev Tu-2 5 turns=Unlock Tu-2
PPSH 42 mass production 6 turns= Increase Rifleman power by +3.
RG-42 grenade 3 turns=Unlock RG-42 grenade with lower cooldown

I think better names for first 2 upgrades are "Better Engeneering I/II"
Also they need more upgrades to unlock other units.

This idea seems a bit to ambiguous, is there any historical reasoning behind these techs?

Well for the war 1941-1945 fost of T-34 while it was improved was halved for example.
For PPSH 42 it was the most producted smg gun in soviets. Not from beginning but at the end of war on EACH soviet soldier (including tank soldiers and pilots!) there were 2,5 these PPSH 42.

okay an for the rest?