Ok.. the Airizer is an "aromatherapy" device. It works differently than an Ecig. Your device is what's called a regulated device. It has different settings for different heat that you want. It has both a vaporizer and a battery in one unit.
With ecigs, it is for the most part totally different. The mech mod you're describing, is simply a metal tube with a 510 connector on top, and an on/off switch. It pretty much works like hooking two wires from the positive and negative of the battery, to the atomizer... no circuitry or electronics to protect the battery from shorting. They can be dangerous if you don't know what you're doing, and most starting vapers don't know.
If I had to build my own starter kit, I'd recommend an
Istick 30 with an aspire
Nautilus tank for starters. the istick 30 has a built in battery, but they are well known devices and have been proven pretty reliable.
Another kit I recommend, is a
subox mini kit. The unit itself is good, but the atomizer might be a bit much for a starting vaper, so I'd probably recommend buying an additional
Nautilus atomizer for her to start with and shelf the subtank atomizer if she decides to stick with it. That would give you such a huge range, and you probably wouldn't have to buy new devices in the future if she stuck with it.