The problem with the M3 is that it has a very small window of usefulness. It's only really useful for killing weapon teams in the early game. It can't do anything vs. gren spam, and it's almost entirely negated once a .222 hits the field. It is exactly a flamethrower delivery system.
So true. I am okay with it being as fragile as it is. However, the damage it does just doesn't impress me. I mean it does some damage, but really the only way to think of it is as a delivery system for flamers. The German car at least can vet up and be a threat. This thing though not so much. It is actually the standard problem with German vs Soviet stuff. Many German units have good upgrades that allow them to vet easier by increasing the damage they do. Only a few of the Soviet units have this option.
As for Penals, I would actually like to see the satchel charge do more damage so it could destroy bunkers.
I actually really like Penals. Not to say I wouldn't take a buff though. The satchel charge is nice because it can punish those that charge them (if you time it well and the opponent isn't paying attention). I think that is the same reason they have the flame thrower (to keep the enemy at distance). Too bad it doesn't really work out so well. You really want a long range weapon as an upgrade so that they can do more damage at range.
Penals are great once you get them vetted up. The thing is though, you often need to land a few satchels to make that happen in a reasonable amount of time.
It would be nice though if they could throw the satchel charge and not have to back up to avoid taking damage.
Overall, when I play Tier 1 the thing I fear most is the Scout Car to Halftrack build. I avoided using guards forever and you simply cannot compete in any way if you are Tier 1 and they have the Scout Cars and Halftrack out(okay, you can if you get lucky with an AT grenade or mine on the Scout Car). However, the Halftrack is going to dominate.
I am open to any tips as Tier 1 (beyond using guards or T70 rush) to deal with a heavy light vehicle build from the Germans.