How are you producing that many tank hunters and still fielding enough cons to make the most out of rapid conscription AND put out a howitzer? Or at least a few 76s or 85s.
The most important thing is teamplay. But let me tell my build first (3vs3/4vs4 AT team):
T0 - 3 to 4 Cons
Upgrade: Healing
Upgrade: sometimes molotov (if there are many ambient buildings and opponents are defensive)
Upgrade: sometimes AT-Grenade (if there are many Kubels/222 around)
T2 - sometimes 1-2 mortars (if opponents are digging in)
Upgrade: AT-Grenade (if not purchased already)
T3 - T70, then another T70 or SU-76
from there more T70/SU-76
or T4 with SU85
or Artillery piece
So its only a rough build order that variates slightly from game to game. You'll see no tank hunters in this build because I always call them on opportunity to kill a light vehicle/tank or finish off a damaged medium/heavy tank that would have escaped otherwise.
So, lets move on to your question. Cons have cheap reinforce costs, partisans are expensive to reinforce and you can't merge with them. If you loose to many you can't afford tech and other more expensive units. So you want to minimize casualties in their ranks. The main threat is enemy AI infantry, so always try to bring your cons wit ppsh in first, use units like T70 in addition to target enemy AI infantry and force a retreat. The german shrek is so effective that your Partisans can take almost any german tank frontally. Once you get one salvo off, toss your AT-grenade in and finish it off afterwards.
But as I said in the beginning: teamplay is key. Play with a mate that offers a lot of AI options like the soviet anti infantry commander to minimize your Partisan looses. If this works out you can afford higher tech units. If not you are nailed at T2 or T3. I had bloody tough games already were I never got past T2 and never got more than maybe 50 population (but my mates did for sure)because I was constantly manpower drained and floating a whooping 500 fuel, but we still won. Despite suffering heavy partisan looses they did this precious key actions, because they killed multiple low health Panther/Tiger/KTs and mined half of the map, heavily restricting enemy vehicle movement. The difference between axis heavy armor driving away with 50 health points left or getting destroyed is such a big one that it can totally compensate your heavy manpower loss. Just be an irreplaceable part of your team.