Soviets suck isn't due to poor balancing, but rather its inflexible design. When you have a developer saying something like this -
The Soviet's are designed to lack flexibility relative to the Germans. You aren't meant to get more than 1 late tier building.
- you know Soviets are pretty fucked. Early game soviets commit to T0 Conscripts or T1 Penals; T1 pretty much requires a doctrine with Guards so they don't get faceraped by Scout Cars. This means locking in a commander early at 2 - 3 CP (6 minutes) so the Germans can wait and counterpick. This limits their late game options.
If you wait till mid game onwards, Soviets are now faced with 3 options on their late game plan:
- Wait for call-ins
- Tech T3
- Tech T4
Waiting for call-ins is arguably the most popular decision at the moment. It bypasses the need for 140 fuel tech (which is steep for what you get). But, you're left with expensive T34/85s or IS2 as your end game solution. T34/85s are pretty decent tanks with good DPS, health, and mobility, and can deal with German T3 on its own, but I'm not sure if sacrificing a 130 fuel tank for a RNG ram against Tigers are a good decision. The worst part is the crew shock duration is so damned short it might as well not happen, for the degree of sacrifice the Soviets just gave up!
The problem with the IS2/KV8 commander is that the Soviet faction loses so much momentum going forward from 8 minutes on, just WAITING for 9 or 10 CPs to click in so they can call in their tank. A Soviets may have Cons/Pens/Maxims/Zis/Snipers, and they're just stalling and stalling from 6 CP onwards just waiting for the CP to tick up. They can't exactly build T3 or else they won't be able to afford the IS2 in a reasonable time frame. They can build fuel caches and stock up on fuel plenty, but they can't do a damn thing till 20 minutes roll around. Soviets are just stuck between a rock and a hard place. The IS2 is a very good tank in and of itself and doesn't require much change. Ideally I'd like to see it as expensive as a Tiger 720/200, and a tad less AI capabilities. The Germans don't bleed manpower (or fuel, for that matter) to the same degree Soviets do and I don't see why it's less expensive, despite being inferior in stats.
Then, you have T3 or T4 tech. T3 provides all-around AT / AI capabilities but nothing truly hard hitting. The 80 penetration of T34/76 is especially frustrating against P4s, suffering massively to the RNG gods. The only way T3 comes out ahead is to keep the German T3 units to an absolute minimum (1 at most); once German T3 gains momentum, Soviets are really at a loss in late game flexibility. If T3 relies on T2 Zis guns to truly bring pain onto German tanks, than Soviets lose all their mobility advantage (engage at rear) as T34s can realistically only operate reasonably close within a ZiS gun's range. Arguably, German tanks with Blitz (from across the whole map with no penalties/engine overheat, no less) is the more mobile of the tank armies.
T4 is a love/hate relationship. One one hand, the Su85 is the hardest hitting AT Soviets have and a nightmare for Germans to deal with because of its 60 range. On the second hand, building each Su85 for 115 fuel means it's a 115 fuel paperweight that cannot push. It's a unit that exclusively deals with tanks. It doesn't deal with any sort of Grenblobs or PGblobs; it just sits in the back and tries its best to deal damage. None of the T4 units can actively hold ground against aggressive German pushes. Su76 barrage is nice but it is centralized in a spot; Katyushas fire rockets slowly in waves and deal nearly zero damage to armor.
If you tech switch, that's the fuel equivalent of building an additional Panther, which means you're already one tank behind before you considered building your Su85 to compliment whatever else.
Now, imagine for a second if you were playing Zerg, which the Soviets are sort of like - cheap, shitty units. You've done your timing pushes with Roaches and Zerglings (low tech, low cost-effective units) and Terran just responded with Mech (Seige Tank, Thor). You want to respond with Swarm Hosts or Mutas, but surprise! Both tech buildings (enabling you to build that unit) cost 500 gas each.