The only item I generally end up using from the amenity kits is the lip balm. I find that whenever I am in Florida the climate makes my lips dry up and crack (& hurt like hell I hasten to add). It's the mix of the warm / humid weather & the cold air-con. I do use the Change for Children envelope on the return flight to ditch all my US loose change smaller than a quarter.
TBH, the amenity kit is pretty naff, even in UC. 2p biro. 2p toothbrush, with thumbnail of toothpaste tube. You get the drift. I think Virgin claimed in the past when they put the "extras" of the amenity kit on the bar, they all got taken.
I'd far rather see no amenity kit & have the basics available on demand (& of decent quality / size). On Emirates in J there is no amenity kit - but in the toilets you can get proper toothbrushes, toothpaste (not a thumbnail tube), combs, razors & shaving foam etc).
I think the way forward is either to do an "all bells & whistles" amenity kit - which only one of the ME3 will do, in First - or ditch it and make it self-serve / on demand and increase the quality of the products.
I actually found a Virgin amenity kit pen from Economy the other day in a drawer - from about 2004 (slightly see-through fluorescent yellow in colour). It puts the current 2p biro that you get in Upper Class to shame!