The 15cm sIG 33 B Sfl (“15cm sIG”) is currently slated to be added to BR II in the upcoming event. I believe it should be moved to BR III for the following reasons:
Recent move of Pz3N from BR II → BR III
DF just moved the Pz3N from BR II → BR III due to it’s oppressive HE ruining the new player experience (and that was only a 75mm shell). Now to be fair, the Pz3N had a 3.3s reload, an MG, and armor compared to the 15cm sIG which has none, but the 15cm sIG has it’s own advantages in being able to overpressure all BR 1 and II tanks as well as nuke objectives in a way the Pz3N could not.
There are already worse vehicles at BR III due to caliber of their gun
The 15cm sIG is open topped, has no MG, and lacks armor; this also describes another tank sitting at BR III: the Dicker Max. The Dicker Max only has a 105mm (compared to the 150mm of the new tank), and yet it is forced into BR III because of the size of it’s cannon
15cm sIG has better HE and Reload then KV-2 at BR IV
A 150mm HE shell has no reason to be in BR2. The 15cm sIG has more explosive mass than the KV-2 (8.6kg vs 5.8kg) which sits at BR IV and also shoots 3x as fast (11.1s vs 33.3s reload).
15cm sIG
KV-2
Understandably the 15cm sIG should be a lower BR than the KV-2 due to the lack of armor/open top. However, the KV-2 can already kill KT(H) shooting the front of the turret as well as anything else the Germans bring in their TT, the 15cm sIG will be able to do the same to all the BR I and II tanks the US or Soviets bring but even faster. I have gotten 32 kills with one shot from the KV-2, the 15cm sIG will be able to do the same but 3x as often. It also sees lower tier maps that are much more open. Tunisia and Moscow both have many open maps where HE fragments can go far and wide. And there is the infamous Bulge map where it is just tanks firing down into a bowl.
BR I players will have to face it
This is the biggest reason for me personally. BR I is where the newest players reside. They are the game’s lifeblood and need time to adjust to all the mechanics of the game, learn maps, get some gear. They need sufficient time to get hooked and should be protected from egregious weapons/gear. I often go down to BR I to use some of my funny premium squads/weapons (Lebel, Moschetto, M44L, SPAA, etc) and 9/10 I am the only player with the ability to deal with grey zone tanks as I have an 11 slot lineup with both planes and tanks, as well as an understanding of how to use my AT rifles or flank to be able to sprint to the tank.
New BR I players only have 4 slots, 3 infantry and either a tank or a plane. They don’t have maxed out squads with perked out guys, they only have AT rifles (if they even unlocked them), and their options are very limited. I know when I first started playing, planes were overwhelming and even with tanks I would often die being useless just getting my bearings. In many of my BR I uptiers, I just watch as one team’s M13/Pz2c/T60s get farmed over and over by the BR II players on the other team who know the tank spawns and how to camp them. The 15cm sIG will just make that even worse. And it will allow for nuking the enemy team over and over when they have incomplete squads with no real way to counter it.
Conclusion
Move the 15cm sIG to BR III. It is more consistent with prior balance changes and current vehicle BRs with the added bonus of protecting BR I until they are able to get to BR II and unlock some more powerful tanks/AT/planes.