I know it was a fun game, but not shooting the looters bothered me.
Looters were the biggest threat to your army, as they were one of the few units that could reach out and shoot you. On your turn 3 when you pointed all those venoms at that one storm boy, you should have pointed them at the looters and at least forced them to go to ground.
Ideally though, shooting 2 venoms at the looters in the ruin turn 1 and every turn after that would have forced enough saves to make them go to ground (halving their damage output before taking into account casualties). Not to mention if you force a leadership test on them, they could run off the board, or lose more models due to the mob rule.
Thanks for sharing the pain.