I feel that there currently is an imbalance between Axis and Allied anti-tank weaponry. I will be talking primarily be talking about tanks and tank destroyers. Here is a good thread about the imbalance bewtween Axis and Allied handheld AT:
http://www.coh2.org/topic/26914/the-imbalance-between-allied-and-axis-infantry-anti-tank
I will now quickly go over some of the Axis tanks
Tiger
This unit is balanced.
Panther
This unit seems fine, but i don't think the buff it got to its armor (to 320) several months ago was necessary. It just needed to be more accessible. Anyways, it is a good unit
except
when combined with blitz and smoke, then it becomes overpowered. It becomes way too survivable with those two abilities and can leave unscathed when baited into a trap.
King Tiger
I think this unit is OP. It bounces shots like crazy. It can deflect AT guns, Jacksons, Jackson vet ability, Su85s, ISU AP shells, IS2s, etc. I think the gun on it is fine but the tank has way too much armor. Gettng some lucky RNG is the only way to stop these behemoths (other than using B4, or airstrikes). It also has combat blitz, which makes the tank very fast (i think it is silly for a gigantic heavy tank to have this ability).
Jagdtiger
I think this unit is okay since it can no longer shoot through walls and buildings.
Elefant
I think this unit is balanced because it is super slow but has a good gun and good armor.
Allied Anti-tank vehicles (non-doctrinal)
Non-doctrinal vehicles include the Jackson and SU85. These vehicles perform well at stopping Ostheer T3 (Jackson stops it too well). However, these units start to struggle against anything heavier than a Tiger. Every shot becomes a prayer to the RNG gods to roll a penetrating hit. Although multiple Jacksons and SU85s are good against a lone Panther, it still feels unreliable. This is best exemplified when using Jacksons and SU85s against a King Tiger. Shots either chip away at the King Tiger, forcing it to retreat, or shot after shot ricochet away. The King TIger then proceeds to smash through your lines while blowing everything up.
Jackson
Good unit but dies very fast. It is also heavily RNG dependent on tanks like the Panther and heavier. Shuts down Ostheer T3 very well (too well). However, when it does penetrate, it can burst down tanks very fast. Vet ability does bounce off Jagdtigers and King Tigers sadly.
SU85
This unit is very good at vet 3, but also suffers from RNG versus heavier units. It is also really sluggish and suffers from horrendous pathfinding. An example of its unreliability is with its matchup against the King Tiger. It may land shot after shot or fail to penetrate multiple times.
Allied Anti-tank (doctrinal)
IS2
This unit is balanced. It actually seems like it got a ninja buff somewhere because the gun can actually do some splash damage to infantry now.
ISU
After the many nerfs, i think this unit is balanced now. However, i think an increase in the penetration of its AP round wouldn't make the unit overpowered. It still struggles to pen the King Tiger even using the AP round. It also bounces off the Panther occasionally. It is sad that even the mighty
Zveroboy is broken against the armor of heavier German tanks.
Final Points
I believe the main imbalance between Axis tanks and Allied are:
1. Axis tanks can consistently penetrate Allied armor (which is okay)
2. Allied tanks cannot consistently penetrate Axis armor, particularly heavy tanks like the King Tiger and Panther.
This leads to weird scenarios where RNG can factor in and give Allied players an edge during tank fights, or get utterly destroyed.
It also does not help that the panzerschreck is very deadly and easily available to units like the Volksgrenadier and Panzergrenadier. These units make an excellent screening force for Axis vehicles because it constantly disrupts Allied tank positioning, giving time for Axis tanks to land some shots. It also acts as a defensive line against flanking Allied tanks. This is another issue that can be discussed in a new thread.
Overall, i think Axis heavies like the King Tiger need an armor reduction. Increasing the penetration of certain Allied tanks could work, but this may be very damaging for Ostheer T3 play.