The Moto G has Assist already although it doesn't have the drive option that the X has. But based on a response to a posting I saw it looks like Motorola has plans to do something similar for the g. The gimmicky features are the other two you mention. Active display is the most interesting but touch less control is something I'd use to show my mates once and never use again. I'm not saying that they are no use to anyone but my point is that they are not so good as to justify the more than double the price tag of the g and more than a better spec nexus 5...
Part of the purpose of releasing the X may be to show off how cheap the G is -- it's a fairly common marketing gimmick. It turns out you can sell a lot more moderately priced widgets if it's shown on the same page of the catalog as a really overpriced widget that's just a little nicer.
Touchless display can be handy while driving. Other than that, it's pretty useless.