Was a nice back and forth I thought until the King Tiger hit , destroying my Flak base was a kick in the nuts as I had to get a Jagdpanzer and some wee at guns. That was probably your window of opportunity as I had to stall out, but t4/t2 is not great at pushing.
I'd probably have gone another Kat or two instead of T3 after t4. Or a quick t3 instead of t4.
Also are starting positions fixed now since last patch? I have not played lots recently but it seems like they are (e.g. consistently getting langre south when Axis or north whilst allies.)
What did you need that JP4 for? You could have saved yourself 145 fuel and gotten the KT that much earlier. SU76 and SU85 do absolutely nothing to infantry with their regular fire and you are not going to catch a katyusha with a JP4. Did you forget about my doctrines and though there were T34/85s coming or something? I'd actually dare say that you could have skipped the JP4 and the AT guns and just got 3 more volks and push me of the map with overwhelming infantry and a few panzerschreks.
I actually made a second katyusha at one point, but I cancelled it because it would have cost me too much supply against the inevitable KT, which admittedly came later than I expected.
And I'm not sure about the starting points. I saw cruzz say that they were fixed, and I have noticed myself spawning on the same sides but I have not played enough to draw a conclusion.