Yeah those SU76s did very little. In this game you were also extremely lucky that both SU76s survived due to the 5%hp non-death crit after getting hit by packs 2 times. This happened like 3 times.
I guess your opponent didn't think he could stall long enough to get a panther before getting his tiger ace. He had the fuel for it but just needed the MP. Even if there would be another sherman on the field by that time, I think the TA+panther would have done much better against 3xsherman + 2xSU76 than just the TA vs 2xsherman and 2xSU76. Especially because there were no ZIS3 guns or AT-nade conscripts on the field.
Yeah I got lucky with the pak shots, although I only recalled it happening twice. You are right with the su76s doing very little, but my rationale is that had they not been there, the panther + TA would have been able to withstand one more shot from the Shermans. By then, it would have still been in my favor, but there was the possibility of panther bouncing frontal shots and the tiger ace having enough time to use target weak point.
Tiger Ace doesn't cost any fuel (I believe), and his army was already fairly small. TA + Panther would be much more threatening, but he might have sacrificed too much map control as a result.