Do the inverter Tig machines have a different procedure for welding than the machines that are not inverters? The sharpened tungsten you have pictured has a very long taper on it, is that the recommended method for the inverters? Zirconiated (brown) tungsten would seem to be the better tungsten choice for high amperage aluminum. I found this on ceriated tungsten that might be of interest to you.
The only tungsten that I ever used was the Green and red. So this is all new to me also
Ceriated (Color Code: Orange)
Ceriated tungsten electrodes (AWS classification EWCe-2) contain a minimum of 97.30 percent tungsten and 1.80 to 2.20 percent cerium and are referred to as 2 percent ceriated. These electrodes perform best in DC welding at low current settings but can be used proficiently in AC processes. With its excellent arc starts at low amperages, ceriated tungsten has become popular in such applications as orbital tube and pipe fabricating, thin sheet metal work, and jobs involving small and delicate parts. Like thorium, it is best used to weld carbon steel, stainless steel, nickel alloys, and titanium, and in some cases it can replace 2 percent thoriated electrodes. Ceriated tungsten has slightly different electrical characteristics than thorium, but most welders can't tell the difference.
Using ceriated electrodes at higher amperages is not recommended because higher amperages cause the oxides to migrate quickly to the heat at the tip, removing the oxide content and nullifying its process benefits.