I am level 12 for Soviets and arranged allies team. Yeah, I think I will limit myself to building 3 squads with the kubel, just haven't quite found the balance myself.
I don't agree with much of the content from others in this thread, as I think they're (unintentionally) setting you up to get brutally dismembered by a competent Allied player. Or worse, your entire panzerfusilier blob gone in a shotgun Katyusha/Calliope barrage.
I won't go into high skill bracket stuff as it is unlikely to make much sense at this stage. So some general pointers:
Volks are fairly rubbish infantry unless you outnumber your opponent in squads, but even then only for a short duration. They are most cost-effective being used behind sandbags and even MGs will struggle to suppress them if properly put behind heavy cover. Watch out for grenades. Generally keep enemy infantry at range, you will know when to charge, in time. Few ppl want to charge into StG volks unless they have the numbers.
Fusiliers are highly recommended by many, but the abysmal early game and weaker durability per model compared to volks (same at vet 0, easier to kill models at vet I/II, same at vet III) is understated heavily. Better offensive scaling doesn't help if you're dead before it even comes online.
Ppl don't respect your MG due to its low dps, but it will suppress. Just might take a little longer in the far distance than MG42.
My personal rule of thumb for the kubel: It never lasts as long as you need it to but it will -always- last longer than your opponent wants it to. Use its sight range to scout out MGs so you don't facecheck them with your inf.
Get used to the Battlegroup -> Flak HQ build as you'll be using it a lot. ISG smoke is invaluable and effectively free. Flak HT is very difficult to micro properly so expect to lose it a lot.
No.1 cheese you should expect are clown cars (don't have lone squads and do focus fire it). Two volks will beat a flame engineer clown car if you
stay calm. Shooting it in the rear helps a lot too.
Don't place your HQs near the frontline, you're asking to lose them and the game with it. Recovery is possible but extremely hard. You'll get a feel for the right distance for each map, with time.
Generally speaking, you have an advantage at the start (Sturmpioneer) and lategame. You should expect to feel weaker in the midgame than your opponents as their LV phase is just better than yours unless you go Mech HQ. Mech HQ is a very high micro build and a vehicle loss can set you back horribly. I do not recommend early stuka except against the campiest of enemy players. Lategame is where you begin to outclass them - Obersoldaten you know very well on the receiving end. Pz IV Ausf J is a very hated med tank but expect it to get penned by shots when you need it the most to live. Panther's a Panther, but TDs are
everywhere. JP4 is a very high skill threshold unit due to its tendencies to bug out when moving and general poor handling. But it is a very dangerous Medium/TD killer.