I would recommend you use Linuxcnc's Plasmac config
PlasmaC User Guide
And read the Linuxcnc Plasma primer I put together
Plasma Cutting Primer for LinuxCNC Users
The reason I say this is that if you use a Hypertherm machine with a RS485 interface, Linuxnc can control it for you.
Plus Linuxcnc and a $69 Mesa THCAD card renders the whole concept of a THC obsolete becasue Linuxcnc knows the arc voltage in real time and can control the torch height using its sophisticated all seeing, all knowing motion controller.
Plasmac is more than a THC, its a complete fully integrated plasma controller which the Windows controllers with an external THC can't compete with.
Anyway, I cut a fair bit of 2mm (similar to your 11 ga). You have to remember plasma is a blunt axe compared with a laser cutter. A laser can cut tap ready holes down to M4 (3.2mm dia hole) in that material. At 10mm, I can get a reasonable hole that are great to pop a nutsert in. At 6mm (maybe 5mm at a pinch) I can get a reasonable clearance hole. But the solution is to spot the hole centres with the plasma torch and drill the hole where accuracy is required. Plasmac supports this.
Just Remember air plasma is not high definition plasma which can compete with laser (aside from the work hardened edges). But then again a 45XP is not a $100k high def system either.