That Panther could well have destroyed itself CharlesBronson.
My views are broadly the same as PlanD's - yes I also rate the Tiger highest!
These are the differences:
KV1
The S was IMHO the worst version, the later KV1's were good but not great.
Pz IV
The only German tank that came close to the T34's near-perfect balance of attributes, but never excelled in any area.
Panther D
This was an own goal. Rushed prototype, bad design, quality that was way below the T34's - silly idea. Hopes were pinned on this tank, it's absolute failure destroying German morale (and improving the Soviet's). However it's gun was still very lethal and frightening to the soviets, a few 75mm L70's used as field guns or in PanzerJagers would have been better?
SU-152
Zveraboy 8) - But has a massive reload to match it's mega payload.
Tiger
Unreliabe, used wrongly - but the best all-rounder.
Ferd
Used wrongly. The best vs tanks, but is infantry considered or not??
IIRC some upgraded Ferd's (Elefant's) were used in the closing stages of Kursk? This may be my 1st choice too CharlesBronson.
Churchill
You underestimate this PlanD. The MkIII had 102mm of armour and a 6pdr gun - OK if not excellent.
It was also hard to immobilize, as it's tracks were designed to stand up to extreme punishment.
Pz III
This had well passed it's sell-by date by this point, but could still take on a T34 or KV1 if handled properly.
T34
The best of the /76 versions. Could (and did) take on a Tiger if used craftily enough, though cavalry charges reduced it's effectiveness drastically. Many simply rammed the Tigers.
Tactics need looking at, the Soviets even fired on the move!
The smokescreen the Soviets layed down was the deciding factor IMHO.
There are a few omissions I believe are important:
Canuck Valentine/76
Tetrarch
SU85
SU122