Hi man and welcome!
Regarding your wife, what ever devices you use, try getting some wooden or acrylic drip tips for her. Avoid anything metal, even stainless steel because it is often mostly unpleasant for people that struggle with "space" looking device in their hand.
And about menthol, since you already mentioned you will get Halo g6, try their Menthol Mystic and Menthol Ice flavors, I heard they are stunning... I don't prefer menthol tastes but I am ordering sample pack these days just to try that Mystic juice. In general Halo are top quality e-liquids. Just avoid Captain Jack and Tiki as first time Halo user imo.