Feuersturm is one of my favorite commanders, though I only use it for the Assault Package, the Hetzer and the Rocket Arty.
That's exactly why i opened this thread.
Maybe the current ISG incendiary barrage could be simply merged to an "Special munition" ability. Would provide ISG incendiary rounds and HEAT shells for the Puma = Both tech paths would provide specific advantages.
Replace the truck with an mortar or let the truck lock down resource sectors, the doctrine would be more attractive and as important: It would not need much work from the mod team.